YOUR HARD DRIVE IS ALMOST FULL:
HOW MUCH DATA CAN THE FOURTH
AMENDMENT HOLD
Ismail Cem Kuru
I.
II.
III.
IV.
TABLE OF CONTENTS
Introduction ........................................................................................... 90
Methods of Collecting and Analyzing Information .............................. 95
A. Definitions ..................................................................................... 96
B. Data Collection Techniques........................................................... 96
1. Imaging .................................................................................... 97
a. Visible light ...................................................................... 98
b. Infrared Light .................................................................... 99
c. Radio Light ..................................................................... 100
2. Wiretapping ........................................................................... 101
3. Keyloggers............................................................................. 102
4. Radio Signals ......................................................................... 103
5. Global Positioning System (GPS) Devices............................ 105
6. Fiber Optic Tapping .............................................................. 106
7. Data Copying ......................................................................... 107
C. Data Processing Methods ............................................................ 108
Background ........................................................................................ 109
A. Text of the Fourth Amendment ................................................... 109
B. Property v. Privacy ...................................................................... 112
C. Search v. Seizure ......................................................................... 114
D. Government’s Subjective Intent .................................................. 115
E. Expectation of Privacy ................................................................ 117
1. Knowing Exposure to the Public ........................................... 119
2. Devices in General Public Use .............................................. 120
F. Wiretapping ................................................................................. 121
G. Mosaic Theory ............................................................................. 121
H. Section 215 of the USA PATRIOT Act ...................................... 124
Analysis ............................................................................................... 124
 J.D. expected May 2016, University of Illinois College of Law, M.S. in Industrial Engineering,
August 2013, Southern Illinois University Edwardsville. Thanks to the Honorable Cemil Kuru for being the
beacon of my career. Many thanks to Andrew Leipold for teaching me the Fourth Amendment and his
invaluable comments that contributed to this article. Thanks also to the editorial staff of the Illinois Journal of
Law, Technology & Policy for all their hard work.
89
90
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A. Reasonable Expectation of Privacy in Life ................................. 124
B. Information Gathering is Not Seizure.......................................... 126
C. Acquisition v. Access .................................................................. 127
D. How Much is Too Much.............................................................. 128
E. Level of Suspicion ....................................................................... 129
F. Efficient Law Enforcement, Potential for Abuse......................... 131
Conclusion and Recommendation....................................................... 132
A tree falls down in a forest. If there is no one to hear it, does it make a
sound? What if the tree falling down is your life being collected; your
movement on public streets, your every phone call, your every visit to a
website, and your every e-mail? What if that entity is the United States
government? If the data is collected as a comprehensive record of United
States history, saved on hard drives and it is never looked at, is that still an
unreasonable search or seizure in violation of the Fourth Amendment of the
United States Constitution? This article aims to answer that question.
Data collection is fundamentally different than data access.1 Data
collection, by itself, does not provide any information to the government.2
Therefore, it makes sense to say that only when the data is processed and put in
a logical form the government learns. This article argues that there is no
search within the meaning of the Fourth Amendment when the government
collects data. The search occurs when the government makes sense of the data
by processing it through a computer, or by an individual government official or
a law enforcement officer. The article further argues that a search warrant
based upon probable cause is unreasonable because the mass collected data
reveals much more than can be justified by the law enforcement interest.
Finally this article proposes a preponderance of the evidence standard for
access to collected data.
I.
INTRODUCTION
Humankind has generated 90% of its data in the past two years.3 This
surge in data generation is, in part, a result of increase in electronic devices
that seem to control our lives.4 For example, upon using the Internet to view
1. ANDREW BLANN, DATA HANDLING AND ANALYSIS 2 (2015) (“[D]ata is effectively . . . information,
and we use statistics to interpret this data—to make sense of and extract meaning from it.”).
2. See Michael Pearson, How Does U.S. Data Collection Affect Me?, CNN POLITICS (June 9, 2013,
3:42 PM), http://www.cnn.com/2013/06/06/politics/nsa-verizon-records-questions/ (stating that the U.S.
Government’s policy is to not access collected records “without ‘reasonable and articulable suspicion’ that
they’re relevant to terrorist activity.”).
3. Matthew Wall, Big Data: Are You Ready for Blast-Off?, BBC NEWS (Mar. 4, 2014),
http://www.bbc.com/news/business-26383058 (“Some say that about 90% of all the data in the world today
has been created in the past few years.”); What Is Big Data?, IBM, http://www-01.ibm.com/software/
data/bigdata/what-is-big-data.html (last visited Mar. 9, 2016) (“Every day, we create 2.5 quintillion bytes of
data—so much that 90% of the data in the world today has been created in the last two years alone.”).
4. See George Simos, How Much Data Is Generated Every Minute on Social Media, WERSM (Aug.
19, 2015), http://wersm.com/how-much-data-is-generated-every-minute-on-social-media/ (illustrating the
enormous amount of data generated on a per-minute basis through the use of social media sites by consumers
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this article, you have generated many data points.5 You presumably opened up
a web browser; you entered a query to a search engine; identified this article as
relating to your query; and viewed the article. All of those steps can be used to
improve your life. The search engine might recognize your interest in the
Fourth Amendment and show you relevant news, or it may show you articles
with common characteristics to this one.
There are many advantages to utilizing these data sets. For example, the
movie-streaming service Netflix utilizes data mining6 to determine viewing
habits of its subscribers.7 With that knowledge, it can predict what movies you
would like to watch next, or even what kind of shows it can develop.8 Major
online retailer Amazon.com uses similar techniques to suggest new items that
may be interest to you based on your viewing and purchasing habits.9
The public perception of data seems to be linked to how much benefit it
receives from that use. When the data is used in a way the public deems
beneficial, such as the next movie to watch or what item to buy, such use is
deemed acceptable.10 Therefore when data is put to use for the individual’s
own benefit, the use is acceptable. Yet, website operators want to extract the
entire benefit of such data by selling personally identifiable information to
third parties,11 and even governments.12 Even if website operators do not sell
on their electronic devices).
5. See Data, Data Everywhere, ECONOMIST (Feb. 25, 2010), http://www.economist.com/node/
15557443 (referencing the concept of “data exhaust”—the trail of data points created by internet users that can
be analyzed to derive valuable information).
6. What Is Data Mining (Predictive Analytics, Big Data), STATSOFT, http://www.statsoft.com/
Textbook/Data-Mining-Techniques (last visited Mar. 6, 2016) (“Data Mining is an analytic process designed
to explore data (usually large amounts of data—typically business or market related—also known as “big
data”) in search of consistent patterns and/or systematic relationships between variables, and then to validate
the findings by applying the detected patterns to new subsets of data.”).
7. Roberto Baldwin, Netflix Gambles on Big Data to Become the HBO of Streaming, WIRED (Nov. 29,
2012, 6:30 AM), http://www.wired.com/2012/11/netflix-data-gamble/.
8. Id.
9. Greg Linden et al., Amazon.com Recommendations: Item-to-Item Collaborative Filtering, IEEE
INTERNET COMPUTING, Jan.–Feb. 2003, at 76, https://www.cs.umd.edu/~samir/498/AmazonRecommendations.pdf; JP Mangalindan, Amazon’s Recommendation Secret, FORTUNE (July 30, 2012, 11:09
AM), http://fortune.com/2012/07/30/amazons-recommendation-secret/.
10. Letter from Daniel Castro, Dir., Ctr. for Data Innovation, to Nicole Wong, Dep. Chief Tech.
Officer, Office of Sci. and Tech. Policy (Mar. 31, 2014), http://www2.datainnovation.org/2014-ostp-big-datacdi.pdf (“By helping individuals and organizations make better decisions, data has the potential to spur
economic growth and improve quality of life in a broad array of fields.”); Daniel Castro & Travis Korte, Data
Innovation 101: An Introduction to the Technologies and Policies Supporting Data-Driven Innovation, CTR.
FOR DATA INNOVATION (Nov. 4, 2013), http://www.datainnovation.org/2013/11/data-innovation-101/
(“Individuals use data to make better decisions about everything from what they buy to how they plan for the
future.”); see also Bernard Marr, How Big Data Is Changing Healthcare, FORBES (Apr. 21, 2015, 10:50 AM),
http://www.forbes.com/sites/bernardmarr/2015/04/21/how-big-data-is-changing-healthcare/ (describing the
benefits of data analysis in the context of the healthcare industry).
11. See Fred Guterl, How Much Control Will We Have Over Our Personal Data?, SCI. AM. (Jan. 25,
2015),
http://blogs.scientificamerican.com/observations/2013/01/25/how-much-control-will-we-have-overour-personal-data/ (describing the financial incentives companies have to monetize the valuable consumer data
they have been collecting over the years and the related benefits that would be provided back to consumers by
use of such data).
12. Bruce Schneier, (Big) Brothers-in-Arms: The Global Public-Private Surveillance Partnership is as
Strong as Ever, BLAZE (Feb. 17, 2015, 9:00 AM), http://www.theblaze.com/blog/2015/02/17/the-globalpublic-private-surveillance-partnership-is-as-strong-as-ever/ (“Many countries use corporate surveillance
capabilities to monitor their own citizens.”).
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the information directly, for example Google, which is an advertising
company, generates most of its revenue from targeted ads.13 A 2009 research
report on user expectations on collected data suggests that there is
“overwhelming concern by users about the collection of personal information
and behavioral profiling.”14 The second concern of the user is the lack of
control over the information collected and “for what purposes it may be
used.”15
The government can (and does) utilize data to improve our daily lives. In
the most basic level traffic lights can be designed and coordinated in such a
way to reduce average waiting times in intersections for both motor vehicles
and pedestrians.16 In the most complicated level, the National Security Agency
(NSA) is collecting massive amounts of phone records without regards to any
individualized suspicion for national security purposes.17
Big data analytics can revolutionize law enforcement with its ability to,
“uncover hidden patterns, correlations, and other insights,” in search for
criminal activity.18 Yet, we are reluctant to let government track our lives the
same way as some private corporations.19 With recent news of NSA
surveillance, attentions turned to limiting and controlling the government’s
collection or use of our data.
The Framers could not have imagined the Internet and the possible uses
and abuses of that remarkable technology. Yet, they did imagine the possible
abuse of government’s knowledge of our activities.20
The majority of the Supreme Court was wary of the question whether
constant monitoring of a person’s location through GPS, installed by law
enforcement authorities on the criminal defendant’s automobile without his
knowledge, was a violation of the Fourth Amendment in United States
v. Jones.21 While the court ultimately held that such monitoring was a
13. MICHAEL H. MORRIS ET AL., CORPORATE ENTREPRENEURSHIP & INNOVATION 112 (2010) (“Google
primarily generates revenue by delivering relevant, cost-effective online advertising.”).
14. JOSHUA GOMEZ, TRAVIS PINNICK & ASHKAN SOLTANI, UC BERKELEY SCH. OF INFO.,
KNOWPRIVACY 17 (Oct. 10, 2009), http://escholarship.org/uc/item/9ss1m46b.
15. Id.
16. DDOT Blogger, Signal Optimization and Improving Traffic Flow in the District, D.ISH (Oct. 8,
2013), http://ddotdish.com/2013/10/08/signal-optimization-and-improving-traffic-flow-in-the-district/.
17. Matt Hamblen, Snowden Leaks Furor Still Spilling Over Into Courts, COMPUTERWORLD (Feb. 8,
2016, 12:02 PM), http://www.computerworld.com/article/3030661/data-privacy/ snowden-leaks-furor-stillspilling-over-into-courts-and-4th-amendment-debate.html; Dan Roberts & Spencer Ackerman, Anger Swells
After NSA Phone Records Court Order Revelations, GUARDIAN (June 6, 2013, 9:05 PM),
http://www.theguardian.com/world/2013/jun/06/obama-administration-nsa-verizon-records.
18. Big Data Analytics: What It Is and Why It Matters, SAS, http://www.sas.com/en_us/insights/
analytics/big-data-analytics.html (last visited Mar. 9, 2016).
19. See Doug Aamoth, PRISM Poll: Do You Care About the Government Mining Internet Data?, TIME
(June 7, 2013), http://techland.time.com/2013/06/07/prism-poll-do-you-care-about-the-government-mininginternet-data/ (indicating that consumers care about the government mining Internet data); see also John H.
Fleming & Elizabeth Kampf, Few Consumers Trust Companies to Keep Online Info Safe, GALLUP (June 6,
2014),
http://www.gallup.com/poll/171029/few-consumers-trust-companies-keep-online-info-safe.aspx
(describing the lack of trust consumers have in companies with regards to keeping collected information
secure).
20. See U.S. CONST. amend. IV (stating that the U.S. government’s power to interfere with individuals’
activities is limited—i.e., by prohibiting “unreasonable searches and seizures. . . .”).
21. United States v. Jones, 132 S. Ct. 945, 948 (2012).
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“‘search’ within the meaning of the Fourth Amendment,” they relied heavily
on property-based trespass to decide the case.22 Yet, Justice Alito, joined by
three other justices, stated that they would decide the case under the Katz
framework, and would find long-term monitoring of a person’s location
through GPS a violation of reasonable expectation of privacy.23 Justice
Sotomayor was the fifth vote in deciding the case under property-based
trespass doctrine, yet she wrote a concurring opinion that went a step further
than Justice Alito’s opinion, stating that even short-term GPS monitoring could
run afoul of the Fourth Amendment because it could reveal a lot of private
information.24
If the Court eventually decides that constant GPS monitoring on public
roads is a violation of the Fourth Amendment, it will open up a large avenue
for litigators to argue the line that separates a violation and no violation.
Although GPS tracking is convenient and cost efficient, law enforcement
does not need strict GPS tracking to know where you have been.25 Our online
presence creates enough data in various forms to allow an accurate picture of
your life being drawn.26 One particular example is the knowledge of location
information to the cellular telephone companies.27 When cell phones connect
to the cell towers, the cell towers record the phone identification and the time
of connection in each company’s server, which can then be used to determine a
rough travel route as the cell phone travels from tower to tower.28
There are two distinct points in the data collection process where the
Fourth Amendment may potentially be implicated. The first point is when the
information is initially gathered by the law enforcement agency. The
acquisition can occur in many ways. For example, acquisition occurs when the
traffic camera captures an image,29 or when data is transmitted from a
company such as Google or Facebook.30 The acquisition of data is
fundamentally different than seizure of property or person.31 During the
22.
23.
24.
25.
Id. at 949.
Id. at 962, 964 (Alito, J., concurring).
Id. at 955 (Sotomayor, J., concurring).
See Kate Knibbs, In the Online Hunt for Criminals, Social Media Is the Ultimate Snitch, DIGITAL
TRENDS (July 13, 2013), http://www.digitaltrends.com/social-media/the-new-inside-source-for-police-forcessocial-networks/ (describing how law enforcement officers utilize social media to locate criminal suspects);
You Are Being Tracked, ACLU, https://www.aclu.org/feature/you-are-being-tracked (last visited Mar. 9, 2016)
(explaining how automatic license plate readers are utilized by U.S. law enforcement entities and private
companies to track criminals and “to collect information about citizens’ innocent activities just in case they do
something wrong.”).
26. Knibbs, supra note 25.
27. See In re Application of the United States for Historical Cell Site Data, 724 F.3d 600, 615 (5th Cir.
2013) (allowing the collection of cell site data under the third-party doctrine); Nathaniel Wackman, Note,
Historical Cellular Location Information and the Fourth Amendment, 2015 U. ILL. L. REV. 263, 267 (2015)
(describing “how police and prosecutors are using historical location data from cellular telephone companies
to investigate and prosecute crimes.”).
28. See Wackman, supra note 27, at 270–71 (explaining how cell service providers collect location and
identification information through cell towers).
29. Red Light Camera Enforcement, CITY OF CHI., http://www.cityofchicago.org/city/en/depts/
cdot/supp_info/red-light_cameraenforcement.html (last visited Mar. 9, 2016).
30. Sam Gustin, Tech Titans Reveal New Data About NSA Snooping, TIME (Feb. 3, 2014),
http://time.com/3902/tech-titans-reveal-new-data-about-nsa-snooping/.
31. See Paul Ohm, The Olmsteadian Seizure Clause: The Fourth Amendment and the Seizure of
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acquisition of information, data is either created32 or it is copied.33 As will be
explained further below, the acquisition does not fit well with the traditional
definition of seizure with respect to the Fourth Amendment.
There are two issues to deal with when trying to analyze data collection
using the traditional definition of seizure.34 In many instances, search and
seizure overlap in their protection.35 Yet there is still a recognized
distinction.36 A search may occur when the privacy interest is implicated, such
as listening to a conversation in a phone booth;37 whereas seizure may occur
when the possessory interest is implicated, such as the interest in freedom of
movement.38
First of all, it is not clear whether there is any possessory interest in the
data created on the Internet.39 The Supreme Court, under the false friend
doctrine, has addressed the situations where a third party collects information
and then turns it over to law enforcement.40 Similarly, “[d]ata in its ethereal,
non-physical form is simply information.”41 The second issue is that there is
no interference with the movement or freedom of the information flow.42
Similar to wiretapping, data flow continues between the source and the
Intangible Property, 2008 STAN. TECH. L. REV. 40 (2008) (discussing the traditional definition of “seizure”).
32. For example, a traffic camera creates a collection of data representing the image within its field of
view. Red Light Camera Enforcement, supra note 29.
33. Although in common parlance it is spoken in terms of “turning over” the information to law
enforcement agencies, only a copy of information is delivered, or more likely transmitted. See Gustin, supra
note 30 (illustrating how companies “turn over” information to law enforcement agencies).
34. The seizure, as discussed below, occurs, “when the [law enforcement] officer, by means of physical
force or show of authority, has in some way restrained the liberty of a citizen.” Terry v. Ohio, 392 U.S. 1, 19
n.16 (1968). Similarly, a seizure of property occurs when there is, “some meaningful interference with an
individual’s possessory interests in that property.” United States v. Jacobsen, 466 U.S. 109, 113 (1984).
35. J. SCOTT HARR ET AL., CONSTITUTIONAL LAW AND THE CRIMINAL JUSTICE SYSTEM 275 (6th ed.,
Cengage Learning 2015). For example, while prohibition against unreasonable searches protects your suitcase
from being searched where it stands, prohibition against unreasonable seizures protects you by preventing the
law enforcement with walking away with it.
36. Horton v. California, 496 U.S. 128, 133 (1990) (“A search compromises the individual interest in
privacy; a seizure deprives the individual of dominion over his or her person or property.”); Jacobsen, 466
U.S. at 113 (“A ‘search’ occurs when an expectation of privacy that society is prepared to consider reasonable
is infringed. A ‘seizure’ of property occurs when there is some meaningful interference with an individual’s
possessory interests in that property.”); see also Arizona v. Hicks, 480 U.S. 321 (1987) (holding that the police
officer had seized stereo equipment when he moved it to record the serial numbers); Nicholas Poehl, The
Difference Between Search and Seizure, AVVO (Sept. 1, 2011), http://www.avvo.com/legal-guides/ugc/thedifference-between-search-and-seizure (describing the distinction between the terms “search” and “seizure”).
37. Horton, 496 U.S. at 133; Katz v. United States, 389 U.S. 347 (1967).
38. Jacobsen, 466 U.S. at 113.
39. Id. (“A ‘seizure’ of property occurs when there is some meaningful interference with an
individual’s possessory interests in that property.”); Horton, 496 U.S. at 133 (“[A] seizure deprives the
individual of dominion over his or her person or property.”). The District Court that addressed NSA’s data
collection program considered both collection and use of the data as a search, and not a seizure. Klayman
v. Obama, 957 F. Supp. 2d 1 (D.D.C. 2013), vacated and remanded, 800 F.3d 559 (D.C. Cir. 2015).
40. See, e.g., Smith v. Maryland, 442 U.S. 735 (1979) (involving a telephone company turning over
records to law enforcement officials); United States v. Miller, 425 U.S. 435 (1976) (involving a bank turning
over records to law enforcement officials).
41. Digitech Image Techs., LLC v. Elecs. for Imaging, Inc., 758 F.3d 1344, 1350 (Fed. Cir. 2014).
42. United States v. Jones, 132 S. Ct. 945, 948 (2012) (“Indeed, the success of the surveillance
technique that the officers employed was dependent on the fact that the GPS did not interfere in any way with
the operation of the vehicle, for if any such interference had been detected, the device might have been
discovered.”).
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destination, no one experiences any delays in phone conversations as the call is
recorded or logged by phone companies.43
The second point in the data collection process where the Fourth
Amendment may be implicated is when the information is accessed.44 There
are many reasons to access the collected information. The most obvious is
identification of individuals.45 For example, cities such as Baltimore, Chicago,
and the District of Columbia have networks of video cameras surrounding
areas where crime levels are higher, to identify individuals crimes.46 A more
“benign” reason for accessing such collected information may be for city
development. For example, traffic engineering47 relies on traffic volume in
developing solutions to problems in city traffic networks.48
The purpose of this article is to devise a better way to frame the question
of when a Fourth Amendment violation could occur with respect to
technological surveillance, and subsequently analyze the legality of the use of
data gathered by traffic cameras to monitor criminal activity.
II. METHODS OF COLLECTING AND ANALYZING INFORMATION
The Court never held that “potential, as opposed to actual, invasions of
privacy constitute searches for purposes of the Fourth Amendment . . . . It is
the exploitation of technological advances that implicates the Fourth
Amendment, not their mere existence.”49 However, technological advances
need to be understood before the implications of future law enforcement
exploitations can be analyzed.
This section will discuss devices and methods that law enforcement
agencies can utilize to gather and analyze information. There are two
categories that involve fundamentally different prospects for violating privacy
interests of individuals. First is direct data collection. These devices and
methods involve a police enforcement agency actively creating a system that
gathers information.50 The second is indirect data collection. These involve
data created for purposes other than law enforcement and are acquired, or that
can be acquired, by the law enforcement agencies.51
43. Klayman, 957 F. Supp. 2d at 14. The details of mass data collection will be discussed further.
44. Throughout this Recent Development article, the terms “data analysis” and “data access” are used
interchangeably.
45. Roberts & Ackerman, supra note 17. For example, if an agency has knowledge that a certain
address is suspected of dealing contraband, the agency can also access GPS location data gathered through
various sources to determine who have visited that location.
46. Andrea Noble, D.C. Surveillance Cameras Become Top Crime-Fighting Tools for Police, WASH.
TIMES (June 30, 2013), http://www.washingtontimes.com/news/2013/jun/30/dc-surveillance-cameras-becometop-crime-fighting-/.
47. Traffic engineering is a branch of civil engineering that uses engineering techniques to achieve the
safe and efficient movement of people and goods. ROGER P. ROESS ET AL., TRAFFIC ENGINEERING 160 (3d ed.
2004).
48. Id.
49. United States v. Karo, 468 U.S. 705, 712 (1984).
50. Statistical Language—Data Sources, AUSTL. BUREAU STAT. (last updated July 3, 2013),
http://www.abs.gov.au/websitedbs/a3121120.nsf/home/statistical+language+-+data+sources.
51. Id.
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Definitions
It is beneficial to start by defining several terms used throughout this
Recent Development article.
“Data point” refers to the smallest piece of information collected.52 For
example, a traffic camera may record time and date, the license plate numbers
of the vehicles that come in its view, speed of travel, location, or it may even
take a picture.53 Each of these recordings can be referred to as a data point.
For example, time is one data point, and license plate number is also a data
point. License plate number, removed from the rest of the information, does
not reveal anything. Each of them by themselves are nearly meaningless.
“Data set” refers to a set of data points that have a meaningful
relationship.54 It consists of at least two data points and a meaningful
relationship between them.55 A license plate number by itself is meaningless,
but when you combine a license plate number with a name and build a
meaningful relationship between the two—ownership—you have something
meaningful; that the individual owns a vehicle with the license plate number.
For example, when the traffic camera records a license plate number, location,
and traffic light condition, it would know that a vehicle with the license plate
number has made a red light violation, if and only if the computer system is
programmed to correlate the license plate number with the light condition.56
Take the opposite example where the system is not programmed to make
such a correlation, and the camera simply records passing cars. Now, the data
obtained by the camera has not yet created a meaning. The meaningful
relationship is formed whenever a police officer reviews those tapes recorded
by the camera and sees the red light, a vehicle passing the traffic stop line, and
the license plate number.
Only by building relationships between data points can we obtain
meaningful information. This relationship is necessary to understand the
distinguishing principle between the fundamentally different actions between
the acquisition of the information and access to that information. As it will be
discussed in detail further below, at the acquisition stage data consists of a
collection of data points with no meaningful relationship. When the data is
accessed, however, meaningful relationships occur and consequently a search
occurs.
B.
Data Collection Techniques
Direct data collection is regarded as methods and devices that are more
52. NEW OXFORD AM. DICTIONARY 430 (2d ed. 2005).
53. See Gary L. Wickert & Melissa J. Fischer, Big Brother’s Eye in the Sky: Use of Red-Light Cameras
in Accident Litigation, CLAIMS J. (Aug. 7, 2014), http://www.claimsjournal.com/news/national/2014/
08/07/252597.htm (explaining the functions and capabilities of traffic cameras).
54. NEW OXFORD AM. DICTIONARY, supra note 52.
55. Id.
56. Wickert & Fischer, supra note 53.
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traditionally used by the law enforcement officers.57 In particular, these are the
methods where the law enforcement officer is taking an action that creates
data.58 Some of these devices have been around for a long time, such as
wiretapping and video cameras.59 Yet, especially with regards to video
cameras, recent technological improvements allow more meaningful and
efficient data processing, thereby allowing more effective use of these
technologies.
1.
Imaging
An image is a representation of what a human would see—it is the visual
representation of light.60 Most of the time, what we think of an image is an
image representing the visible light. However, light is not limited to what we
can see.61 Infrared and radio are also forms of light.62 What distinguishes
them is their wavelength and human eyes’ capability to detect them.63 The
map of all the types of light that we can identify comprises the electromagnetic
spectrum.64 The light classes are separated by wavelength, because the
wavelength directly relates to how energetic the wave is.65 Whether a
particular wavelength passes through an object depends on the energy level of
the light wave and the band gap of the atoms comprising the object.66 While
most solid objects reflect visible light, most allow the radio waves to pass
through.67
Human ingenuity stepped up where human eyes have failed, and we have
the capability to detect the entire spectrum of light.68 Different devices and
techniques are used for different light. The prices of such devices vary from
$50 for a point-and-shoot camera to $15,000 for a gamma ray detector as the
materials required to detect certain light is much more expensive than others.69
57. See Justine Brown, Law Enforcement Agencies Face Complex Data Challenges, GOV’T TECH. (July
20, 2015), http://www.govtech.com/data/Law-Enforcement-Agencies-Face-Complex-Data-Challenges.html
(describing various ways police officers collect data, such as body camera footage, fingerprints, and
surveillance video footage).
58. AUSTL. BUREAU STAT., supra note 50.
59. History and Evolution of the Video Camera, LIVEWATCH, https://www.livewatch.com/history-andevolution-of-the-video-camera (last visited Mar. 9, 2016); William Lee Adams, Brief History: Wiretapping,
TIME (Oct. 11, 2010), http://content.time.com/time/magazine/article/0,9171,2022653,00.html.
60. Valentin Dragoi, Chapter 14: Visual Processing: Eye and Retina, NEUROSCIENCE ONLINE (1997),
http://neuroscience.uth.tmc.edu/s2/chapter14.html.
61. Molly Read, Electromagnetic Spectrum, U. WIS., http://cmb.physics.wisc.edu/pub/tutorial/
spectrum.html (last visited Mar. 9, 2016).
62. Id.
63. Id.
64. Id.
65. Id. However, the categories that separate certain wavelengths are somewhat arbitrary and may
overlap. For example, x-ray (generated by electrons in the atom) and gamma ray (generated by the nucleus in
the atom) categories overlap at the high-energy boundary, and they are separated by their source.
66. Wave Behaviors, NASA.GOV, http://missionscience.nasa.gov/ems/03_behaviors.html (last visited
Mar. 9, 2016).
67. Id.
68. Although this may be misleading since we only named the regions of electromagnetic spectrum that
we can detect. Theoretically, the shortest wavelength can be as small as a marginally longer wavelength than
the smallest particle of universe.
69. See HASTINGS A. SMITH, JR. & MARCIA LUCAS, LOS ALAMOS NAT’L LAB., PASSIVE
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These technologies are commonplace. We are all familiar with movies
where photographs of a suspect walking into a victim’s home are found and
shown at trial. Images document what is there, precisely. Although images
can be altered,70 these alterations can be detected.71
Fundamentally, what images do is provide information about a certain
physical characteristic of the environment.72 It provides that a certain light is
being emitted or reflected by objects.73 A camera shows the visible light,
whereas a thermal imager shows the infrared light.74 Only after an image is
formed or information regarding the light is obtained, do we draw conclusions.
Further, each category of light gives us different information. If we
detect that gamma ray radiation is radiating from a house, then we know there
must be a radioactive material in the house because they do not occur naturally
in the house.75 Similarly, if we detect the infrared light coming from the
house, then we can infer about the use of the house.76 Unlike gamma rays,
however, infrared light can tell us much more than just the existence of one
particular type of material.77
a.
Visible light
Although the history of cameras dates back to the sixteenth century, until
the invention of photography—and the discovery that some substances are
altered by exposure to light—in the early nineteenth century, there was no way
to preserve the images.78 What was once a costly and time-consuming
endeavor is now a critical part of our culture. The number of photos uploaded
and shared over the Internet has constantly risen since 2005, and in 2014, 1.8
billion photos were uploaded and shared per day.79
Cameras are most commonly used to capture visible light.80 A digital
NONDESTRUCTIVE ASSAY MANUAL 63 (1991) (noting that higher resolution detectors are higher in cost in
regard to gamma-ray detectors); Gamma Ray Detectors, EURSSEM, http://eurssem.eu/pages/c-4-3-gammaray-detectors (last visited Mar. 9, 2016); Point & Shoot Digital Cameras, AMAZON,
http://www.amazon.com/s?rh=n%3A330405011%2Cp_36%3A1253504011 (last visited Mar. 9, 2016).
70. See President of the World, Body Evolution—Model Before and After, YOUTUBE (May 22, 2012),
https://www.youtube.com/watch?v=17j5QzF3kqE&feature=youtu.be (showcasing an extreme example of how
much photograph post-capture editing can affect the outcome).
71. See, e.g., Alexy Kuznetsov et al., Detecting Altered Images, BELKASOFT (Aug. 22, 2013),
https://belkasoft.com/detecting-forged-images (discussing how alterations to images can be detected).
72. Chapter 2—Basic Theory—Electromagnetic Spectrum—Color is Reflected Light, LIFEPIXEL,
http://www.lifepixel.com/infrared-photography-primer/ch2-basic-theory-color-is-reflected-light (last visited
Mar. 9, 2016).
73. Id.
74. See Infrared Waves, NASA, http://missionscience.nasa.gov/ems/07_infraredwaves.html (last visited
Mar. 9, 2016) (noting thermal imaging technology that allows humans to perceive infrared light).
75. See Gamma Rays, NASA, http://missionscience.nasa.gov/ems/12_gammarays.html (last visited
Mar. 9, 2016) (explaining that gamma waves on Earth emanate from radioactive material).
76. See NASA.GOV, supra note 74 (detailing how thermal imaging can be used to detect infrared waves
emanating from any number of sources, including humans).
77. See id. (explaining that many objects emit infrared waves).
78. ROBERT HIRSCH, SEIZING THE LIGHT: A HISTORY OF PHOTOGRAPHY (2000).
79. Mary Meeker, Internet Trends 2015—Code Conference, KPCB (May 27, 2015),
http://www.kpcb.com/internet-trends.
80. Jerry Lodriguss, How Digital Cameras Work, CATCHING THE LIGHT (2015),
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camera includes a digital camera sensor.81 The sensor, in turn, includes tiny
light-sensitive diodes.82 The light hitting the lens is directed to the sensor.83
Light is a form of energy and each diode converts the energy in light into an
electrical current.84 This electrical current is then transferred into an analog-todigital converter, which turns the signal from each diode into a digital value.85
This digital value is the value for a pixel in the image.86 The pixels are then
combined to form an image.87
The major limitation in cameras is that the light must hit the lens. The
camera records what it “sees.” What the camera “sees” depends on the image
sensor used.88 Included in digital cameras commonly used by the public is an
image sensor sensitive to visible light, which includes the wavelengths within
390 to 700 nanometers in the electromagnetic spectrum.89
b. Infrared Light
Infrared light has wavelengths longer than visible spectrum, from 700
nanometers to one millimeter.90 By using diodes sensitive to infrared light
wavelengths, images can be obtained with a camera.91 Usually, false color is
used to differentiate between objects emitting or reflecting higher and lower
intensities of infrared light.92 Thermal imagers use image sensors that are
sensitive to infrared light.93 Thermal imagers are useful in dark environments
because every object that stores heat naturally emanates it as infrared light. 94
The increase in the temperature of the object increases the intensity of the
infrared light.95 Therefore, a difference in the temperature of adjacent objects
allows the individual to distinguish between those objects, just like
http://www.astropix.com/html/i_astrop/how.htm.
81. There are two different digital camera sensors currently used, CMOS and CCD. GERALD C. HOLST
& TERRENCE S. LOMHEIM, CMOS/CCD SENSORS AND CAMERA SYSTEMS (2d ed., JCD Publishing 2011); see
also John Wenz, These Simple Animations Show How Digital Camera Sensors Work, POPULAR MECHANICS
(May 8, 2015), http://www.popularmechanics.com/technology/a15436/heres-how-the-cmos-and-ccd-sensorswork/ (showing an animation of how this technology works).
82. Lodriguss, supra note 80.
83. Id.
84. Id.
85. Id.
86. Id.
87. Id.
88. Imaging Electronics 101: Understanding Camera Sensors for Machine Vision Applications,
EDMUND OPTICS, http://www.edmundoptics.com/resources/application-notes/imaging/understanding-camerasensors-for-machine-vision-applications/ (last visited Mar. 9, 2016).
89. Id.
90. What Wavelength Goes with a Color?, NASA, http://science-edu.larc.nasa.gov/EDDOCS/
Wavelengths_for_Colors.html (last visited Mar. 9, 2016); see also JOHN AVISON, THE WORLD OF PHYSICS (2d
ed. 2014).
91. Do Young Kim et al., Multi-Spectral Imaging with Infrared Sensitive Organic Light Emitting Code,
NATURE (Aug. 5, 2014), http://www.nature.com/articles/srep05946#close.
92. Rhett Allain, The World Looks Different Through an Infrared Camera, WIRED (Apr. 9, 2014, 6:19
PM), http://www.wired.com/2014/04/the-world-looks-different-when-you-see-in-infrared/.
93. Id.
94. Id.
95. Id.
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distinguishing between two objects emanating (or reflecting) visible light.96
Although thermal imagers are much more expensive than the visible spectrum
cameras, thermal imagers can now be purchased as an add-on for digital
phones such as the iPhone.97
Night vision goggles also utilize infrared light, only at a lower
wavelength and nearer to the visible spectrum.98 An infrared light source
positioned on the night vision goggle shines infrared light into the view of the
user.99 The goggles also include sensors capable of detecting infrared light
reflected from nearby objects, and using false color based on intensity, the
goggles show an image to the user.100
c.
Radio Light
Radio waves are a form of light.101 Radio waves include the wavelengths
between one millimeter and 100 kilometers in the electromagnetic spectrum.102
Radio waves can naturally be made by lightning or by astronomical objects.103
Radio waves can be used to create images.104 Further, objects in common use
reflect radio waves just like any other light wave.105 Because neither people or
common household objects naturally emit radio waves, it is not possible to
create an image of a closed enclosure, such as a house, from the radio waves
emanating from inside the enclosure similar to thermal imagers.106 However, it
is possible to use a device to send radio waves with known wavelength and
intensity, detect the reflected radio waves and determine whether a particular
object, or person, is in the house,107 or get an accurate “image” of the inside of
96. Id.
97. See, e.g., FLIR ONE, http://www.flir.com/flirone/ (showing an example of an app-based thermal
imager).
98. Infrared Waves, NASA, http://missionscience.nasa.gov/ems/07_infraredwaves.html (last visited
Mar. 9, 2016).
99. Kendra Rand, Infrared Light, PHYSICS CENT., http://www.physicscentral.com/explore/action/
infraredlight.cfm (last visited Mar. 9, 2016).
100. How Night Vision Works, SOFRADIR-EC, http://sofradir-ec.com/hownightvisionworks/ (last visited
Mar. 6, 2016).
101. Anatomy of an Electromagnetic Wave, NASA, http://missionscience.nasa.gov/ems/02_
anatomy.html (last visited Mar. 9, 2016).
102. CONCISE DICTIONARY OF SCI. 253 (2012).
103. Id.
104. Radar is the use of radio waves to detect objects. Emily Lakdawalla, How Radio Telescopes Get
“Images” of Asteroids, PLANETARY SOC’Y (Nov. 8, 2011, 4:52 PM), http://www.planetary.org/blogs/emilylakdawalla/2011/3248.html.
105. Ian Poole, Electromagnetic Waves—Reflection, Refraction, Diffraction, RADIO-ELECTRONICS.COM,
http://www.radio-electronics.com/info/propagation/em_waves/electromagnetic-reflection-refractiondiffraction.php (last visited Mar. 9, 2016).
106. Thermal Imaging: Facts vs. Fiction, P&R INFRARED, http://pr-infrared.com/about-thermal-imaging/
thermal-imaging-facts-vs-fiction/ (last visited Mar. 9, 2016).
107. As will be discussed later in this Recent Development article, the Tenth Circuit has addressed the
use of such a device to determine if a suspect was inside the home before executing a search warrant. United
States v. Denson, 775 F.3d 1214, 1219 (10th Cir. 2014) cert. denied, No. 14-9128, 2015 WL 1468640 (U.S.
May 4, 2015); see also Brad Heath, New Police Radars Can “See” Inside Homes, USA TODAY (Jan. 20, 2015,
1:27
PM),
http://www.usatoday.com/story/news/2015/01/19/police-radar-see-through-walls/22007615/
(suggesting at least fifty U.S. law enforcement agencies are utilizing radar devices to scout homes).
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the enclosure by using several devices from different angles.108
2.
Wiretapping
Wiretapping technology, even if it is newer than photography, is not
new.109 Wiretapping is authorized by a series of federal and state statutes.110
Wiretapping is a broad term, which encompasses many methods of
intercepting communications. It receives its name because in the days of
landline phones, the wires that composed the landline needed to be altered to
redirect signals traveling along the wire to another location.111
Yet, it is possible to “wiretap” without physical intrusion.
Communications over radios can be “tapped” using a radio frequency receiver
operating at the same frequency as the radios.112 There are technical—even if
not conceptual—differences in the tapping method based on the technology
being used. Further, in the context of communications through the Internet,
there are many points between the communication initiator and the intended
recipient where a communication can be intercepted, recorded, or copied.
To illustrate these concepts, take for example, an e-mail communication
between Jack and Sally. Jack types the e-mail address into his browser.
Whatever is typed on a computer can be recorded and transmitted to a third
party using specialized software called a keylogger.113 The e-mail either
travels to a wireless router using radio waves over the air or to a wired router
using electrical current over an ethernet cable.114 Radio waves can be obtained
using an appropriate radio receiver operating at the same frequency.115 Wires
can be tapped by intercepting the electrical current during its travel.116 Next,
the router sends data representing the e-mail to an Internet Service Provider
(“ISP”) using fiber optic cables.117 Fiber optic cables are hollow tubes that are
108. This technique is similar to a CAT scan in a hospital, which uses hundreds of x-ray scans from
different angles to create a 3D image of the tissue. Computed Tomography (CT)—Body, RADIOLOGYINFO.ORG
(Sept. 23, 2014), http://www.radiologyinfo.org/en/info.cfm?pg=bodyct.
109. William Lee Adams, Brief History: Wiretapping, TIME (Oct. 11, 2010), http://content.time.com/
time/magazine/article/0,9171,2022653,00.html.
110. See ADMIN. OFFICE OF U.S. COURTS, WIRETAP REPORT 2013, TABLE 1 (2013),
http://www.uscourts.gov/uscourts/Statistics/WiretapReports/2013/Table1.pdf (listing jurisdictions with statutes
authorizing wiretapping activities).
111. See R. SHIREY, IETF TRUST, INTERNET SECURITY GLOSSARY 336 (2d rev., Aug. 2007),
http://tools.ietf.org/html/rfc4949 (stating that “[a]lthough the term originally referred to making a mechanical
connection to an electrical conductor that links two nodes, it is now used to refer to accessing information from
any sort of medium used for a link or even from a node, such as a gateway or subnetwork switch.”).
112. Radio waves can be captured with any radio receiver device configured to the same frequency as
the radio wave. Catch a Wave: Radio Waves and How They Work, ILLUMIN [hereinafter Catch a Wave],
http://illumin.usc.edu/114/catch-a-wave-radio-waves-and-how-they-work/ (last visited Mar. 6, 2016).
113. Nikolay Grebennikov, Keyloggers: How They Work and How to Detect Them, SECURELIST (Mar.
29, 2007, 1:03 PM), https://securelist.com/analysis/publications/36138/keyloggers-how-they-work-and-howto-detect-them-part-1/.
114. How Does Wirelesss Internet Work, WIRELESS TECH. ADVISOR, http://www.wireless-technologyadvisor.com/how-does-wireless-internet-work.html (last visited Mar. 9, 2016).
115. Catch a Wave, supra note 112.
116. Fact Sheet 9: Wiretapping and Eavesdropping on Telephone Calls, PRIVACY RTS. CLEARINGHOUSE,
(Feb. 2016), https://www.privacyrights.org/content/wiretapping-and-eavesdropping-telephone-calls.
117. Exploring the Modern Computer Network: Types, Functions, and Hardware, CISCO (Dec. 19,
2013), http://www.ciscopress.com/articles/article.asp?p=2158215&seqNum=6.
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covered with reflective coating, and information is carried using light.118 It is
possible with a technique not unlike wiretapping to direct some of the light
traveling through fiber optic cable to a third location and extract
information.119 The ISP receives the e-mail in a local Point of Presence server.
It then redirects the e-mail to an Internet Exchange Point (“IXP”) server.120
Each IXP server connects many ISP servers, and each IXP server is connected
to one or more other IXP servers.121 Every time the e-mail reaches an ISP
Point of Presence server or an IXP server, it is stored briefly in a data center.122
Whatever data is stored in the IXP can be copied to a secondary data center
without affecting the journey of e-mail from Jack and Sally.123 In fact, most email servers (Google, Microsoft, Yahoo, etc.) store a copy of the e-mail on
their computer.124 The e-mail then follows a similar path—ISP, router,
computer—to reach Sally’s browser.125
Now that we know where the information can be copied, we can continue
to discuss how this is accomplished.
3.
Keyloggers
Computers can be tapped by installing specialized software called a
“keylogger.”126 Keyloggers record every keystroke made by the user of the
computer on which it is installed.127 They can also be programmed to transmit
the collected data to another computer when it is connected to a network or
Internet.128 Although it is generally used for criminal purposes, or spying on
118. Information transferred using light is faster because light travels faster than electrical current and
there is less resistance (therefore less loss of power) along the travel. How Fiber-Optic Internet Works,
BEACON, http://fios.verizon.com/beacon/how-fiber-optic-internet-works/ (last visited Mar. 9, 2016).
119. U.S. Patent No. 6,535,671 (filed Feb. 27, 2001); see also KIMBERLIE WITCHER, FIBER OPTICS AND
ITS SECURITY VULNERABILITIES 8 (Feb. 17, 2005), https://www.sans.org/reading-room/whitepapers/physical/
fiber-optics-security-vulnerabilities-1648 (stating that “[t]o do a virtually undetected tap, it is almost certain
that intruders would only need available commercial items, such as, a laptop, optical tap, packet-sniffer
software, and an optical/electrical converter.”).
120. What Is an Internet Exchange Point?, NETNOT https://www.netnod.se/ix/what-is-ixp (last visited
Mar. 9, 2016) [hereinafter What Is an IXP?].
121. See generally PATRICK S. RYAN & JASON GERSON, A PRIMER ON INTERNET EXCHANGE POINTS FOR
POLICYMAKERS AND NON-ENGINEERS (Aug. 11, 2012), http://ssrn.com/abstract=2128103 (describing the
architecture of IXP servers and systems).
122. What Is an IXP?, supra note 120.
123. See generally, INTERNET SOC’Y, THE INTERNET EXCHANGE POINT TOOLKIT & BEST PRACTICES
GUIDE (Feb. 2014), https://www.internetsociety.org/sites/default/files/Global%20IXPToolkit_Collaborative%
20Draft_Feb%2024.pdf (summarizing IXP distribution protocols).
124. See, e.g., Benjamin Mako Hill, I Don’t Use Gmail, but Google Still Has Lots of My Personal
Emails, SLATE (May 13, 2014, 2:03 PM), http://www.slate.com/blogs/future_tense/2014/05/13/don_t_
use_gmail_here_s_how_to_determine_how_many_of_your_emails_google_may.html (discussing Google
servers storing copies of sent and received e-mails).
125. See J. KLENSIN, INTERNET SOC’Y, SIMPLE MAIL TRANSFER PROTOCOL (Apr. 2001), http://
www.ietf.org/rfc/rfc2821.txt (showing a simple e-mail transfer protocol); see also JONATHAN B. POSTEL,
UNIV. S. CAL. INFO. SCI. INST., SIMPLE MAIL TRANSFER PROTOCOL (Aug. 1982), http://www.ietf.org/rfc/
rfc821.txt (showing a simple mail transfer protocol example).
126. See OXFORD ONLINE DICTIONARY, http://www.oxforddictionaries.com/definition/english/
keylogger (last visited Mar. 9, 2016) (providing the definition of “keylogger”).
127. Grebennikov, supra note 113.
128. Id.
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friends’ and families’ Facebook accounts,129 it can also be used to gather
information about suspects’ activities on the computer by gathering
screenshots in addition to keystrokes.
One method of delivering a keylogger to a computer is by using a Trojan
horse.130 A Trojan horse is harmful software depicted as useful.131 These can
be planted on websites flagged as dangerous, such as a website used in
dissemination of child pornography, or a website belonging to a known
criminal organization.132 A user visiting the website is asked to download a
software to his computer depicting it as a helpful tool, or as the content the
user is looking for.133 Once a computer user tries to open the software, nothing
happens on the screen.134 The program starts recording and transmitting the
information to a police officer or a third party to be analyzed.135
Smart phones are essentially a small computer, and therefore they can
also be tapped using keyloggers.136
4.
Radio Signals
Radio signals are a form of light with wavelengths ranging from one
millimeter to 100 kilometers.137 Radio signals are potentially the easiest to
capture because they travel over the air and reception of the signal at one
receiver does not affect the transmission of the signal to its intended
destination.138 Both wireless Internet and cell phones operate over the air
using radio frequency signals.139
Cell phones use radio signals to communicate with the cell towers.140
129. Security Spotlight: A Closer Look at Malicious Keyloggers, IOLO, http://www.iolo.com/resources/
articles/security-spotlight-a-closer-look-at-malicious-keyloggers/ (last visited Mar. 9, 2016).
130. Mary Landesman, What Is a Keylogger Trojan?, ABOUT TECH, http://antivirus.about.com/od/
whatisavirus/a/keylogger.htm (last visited Mar. 9, 2016).
131. Id.
132. What is a Keylogger Virus and How to Remove It, COMBOFIX (Feb. 13, 2012),
http://www.combofix.org/what-is-a-keylogger-virus-and-how-to-remove-it.php; see also Trojan Virus Used to
Monitor Criminals in Germany, DW NEWS (Oct. 19, 2011), http://www.dw.com/en/trojan-virus-used-tomonitor-criminals-in-germany/av-6641838 (showing a video of the German Justice Minister detailing a policy
that uses Trojans to monitor convicted criminals on the Internet).
133. Pieter Arntz,
What are Trojans?, MALWAREBYTES LABS (June 4, 2013),
https://blog.malwarebytes.org/intelligence/2013/06/what-are-trojans/.
134. Id.
135. The courts have not yet resolved the legality of wiretapping under the Fourth Amendment. The
courts that have looked at wiretapping did so in the context of the Federal Wiretap Act, 18 U.S.C. §§ 2510–
2522 (2012). See, e.g., Halperin v. Int’l Web Servs. LLC, 70 F.Supp.3d 893, 901–03 (N.D. Ill. 2014)
(examining allegations of wiretapping in the context of the Federal Wiretap Act).
136. See, e.g., iKeyMonitor—Best Android Keylogger, IKEYMONITOR, http://ikeymonitor.com/androidkeylogger (describing and selling an app used to log Android phone activities) (last visited Mar. 9, 2016).
137. CONCISE DICTIONARY OF SCIENCE, supra note 102.
138. STEFAAN SEYS & BART PRENEEL, ARM: ANONYMOUS ROUTING PROTOCOL FOR MOBILE AD HOC
NETWORKS (2006) (discussing why the nature of radio transmissions makes them easier to capture). As an
example, consider the situation where you can turn on two television sets with the same remote at the same
time.
139. Marshall Brian et al., How WiFi Works, HOWSTUFFWORKS (Apr. 30, 2001),
http://computer.howstuffworks.com/wireless-network1.htmhttp://computer.howstuffworks.com/wirelessnetwork1.htm.
140. Id.
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Cell towers broadcast radio signals in frequent intervals.141 When a cell phone
comes in the cell tower range, it replies to the tower with an authentication
code.142 If the tower approves the authentication code, a connection is
made.143 At any given time, a cell phone can be in communication with
several towers simultaneously.144 The frequency of the radio signal depends
on the carrier145 and is regulated by the Federal Communications
Commission.146
Cell phone signals can be intercepted as they travel through the air using
any receiver operating at the same frequency147 because the cell phone
broadcasts the signal in every direction—it does not have the capability, nor
the necessity, to broadcast the signal in a particular direction.148 The
information contained in the radio signals is compressed and encrypted by the
wireless communication companies.149 Yet, these encryptions are not safe.150
Therefore, it is possible to listen in to a phone conversation with relative ease.
One device created specifically for this purpose is commonly called a
Stingray.151 A Stingray device acts as a pirate cell tower.152 It broadcasts
signals similar to that of a legitimate cell tower.153 The signal strength
gradually increases.154 Because cell phones are programmed to connect to the
141. Michael Harris, How Cell Towers Work, UNISON (Mar. 9, 2011), http://www.unisonsite.com/
resource-center/resource.html?article=40 (“The primary job of a cell tower is to elevate antennas that transmit
and receive radio-frequency (RF) signals from mobile phones and devices.”).
142. Cell-Phone Technology, WIKIEDUCATOR.ORG, https://wikieducator.org/images/7/7f/Cell_Phone_
technology.pdf (last visited Mar. 9, 2016).
143. Id.
144. Marguerite Reardon, Turning Cell Phones into Lifelines, CNET.COM (Dec. 8, 2006),
http://www.cnet.com/news/turning-cell-phones-into-lifelines/ (illustrating that through mobile switching
centers, cell phones can be connected to multiple towers).
145. Frequencies by Provider, WILSONAMPLIFIERS (Oct. 12, 2014), http://www.wilsonamplifiers.com/
frequencies-by-provider.
146. 47 C.F.R. § 2.106 (2014); Radio Spectrum Allocation, FCC, https://www.fcc.gov/encyclopedia/
radio-spectrum-allocation (last visited Mar. 9, 2016).
147. Police Use Stingray Tool to Intercept Cellphone Signals, NAT’L PUBLIC RADIO (Aug. 4, 2015),
http://www.npr.org/2015/06/22/416538036/police-use-stingray-tool-to-intercept-cell-phone-signals
(illustrating that certain types of equipment can intercept radio signals over the air).
148. Clay Dillow, By “Beamsteering” Antenna Signals in One Direction, Devices’ Power Consumption
Could Be Halved, POPULAR SCI. (Dec. 15, 2010), http://www.popsci.com/technology/article/2010-12/steeringmobile-device-signals-one-direction-power-consumption-could-be-halved.
149. The Cell Phone Technology, U.C. SANTA BARBARA, http://www.mat.ucsb.edu/~g.legrady/
academic/courses/03w200a/projects/wireless/cell_technology.htm (last visited Mar. 9, 2016).
150. “Speaking at the Chaos Computer Club (CCC) Congress in Berlin on Tuesday, a pair of researchers
demonstrated a start-to-finish means of eavesdropping on encrypted GSM cellphone calls and text messages,
using only four sub-$15 telephones as network ‘sniffers,’ a laptop computer, and a variety of open source
software.” Jon Borland, $15 Phone, 3 Minutes All That’s Needed to Eavesdrop on GSM Call, ARS TECHNICA
(Dec. 29, 2010, 8:58 AM), http://arstechnica.com/gadgets/2010/12/15-phone-3-minutes-all-thats-needed-toeavesdrop-on-gsm-call/.
151. Joel Hruska, Stingray, the Fake Cell Phone Tower Cops and Carriers Use to Track Your Every
Move, EXTREMETECH (June 17, 2014, 4:51 PM), http://www.extremetech.com/mobile/184597-stingray-thefake-cell-phone-tower-cops-and-providers-use-to-track-your-every-move.
152. Id.
153. Id.
154. The Cell Phone Technology, U.C. SANTA BARBARA, http://www.mat.ucsb.edu/~g.legrady/
academic/courses/03w200a/projects/wireless/cell_technology.htm (last visited Mar. 20, 2016); Cellular
Handover and handoff, RADIO-ELECTORNICS.COM, http://www.radio-electronics.com/info/cellulartelecomms/
cellular_concepts/handover_handoff.php (last visited Mar. 20, 2016).
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cell tower with the highest signal strength, when the signal from a Stingray
reaches a critical point, nearby cell phones connect to the Stingray rather than
the legitimate cell tower.155
A Stingray at this point acts as a bridge between the cell phone and the
cell tower.156 It broadcasts signals to the nearby cell towers with the device
identification of those devices that are connected to it.157 When a Stingray
communicates with the cell tower, it conceals itself and acts as the cell phone
would (with the cell phone’s identification and registration codes that it
received when the cell phone tried to register with the Stingray), receives any
incoming information from the cell tower and stores it before transmitting it to
the cell phone.158 Similarly, any information—the device identification, phone
numbers, text messages—sent from the cell phone passes through the Stingray
and can be recorded at the Stingray before being transmitted to the cell tower
or vice versa.159
The capabilities of a Stingray do not end there however. It can
manipulate the transmissions to and from the cell tower or block them
completely; instead of sending a transmission as soon as it receives it, it can
store it.160 Then the user of the device can manipulate the transmission, such
as the contents of a text message, and continue to transmit it to the cell tower
when the modification is completed.161
5.
Global Positioning System (GPS) Devices
GPS is a network of satellites that are positioned around Earth, which
allows for determining the position of a GPS device on Earth. Initially
developed as a military project, GPS uses radio waves to triangulate162 the
position of the receiver. Each GPS satellite broadcasts its position and the
current time at regular intervals.163 When a GPS receiver is activated it
searches for signals from GPS satellites that are broadcasted on two
frequencies.164 The receiver uses this information to calculate its position on
155. Kate Martin, Documents: Tacoma Police Using Surveillance Device to Sweep Up Cellphone Data,
NEWS TRIBUNE (Aug. 26, 2014, 3:56 PM), http://www.thenewstribune.com/news/local/article25878184.html.
156. Id.
157. Id.
158. Id.
159. Clarence Walker, New Hi-Tech Police Surveillance: The “StingRay” Cell Phone Spying Device,
GLOBALRESEARCH (May 19, 2015), http://www.globalresearch.ca/new-hi-tech-police-surveillance-thestingray-cell-phone-spying-device/5331165 (discussing the data capturing capabilities of the StingRay device).
160. Id.
161. Hanni Fakhoury & Travor Timm, Stingrays: The Biggest Technological Threat to Cell Phone
Privacy You Don’t Know About, ELEC. FRONTIER FOUND. (Oct. 22, 2012), https://www.eff.org/deeplinks/
2012/10/stingrays-biggest-unknown-technological-threat-cell-phone-privacy.
162. TIM STOMBAUGH ET AL., UNIV. KY. COLL. OF AGRIC., GPS SIMPLIFIED (2002),
http://www2.ca.uky.edu/agc/pubs/pa/pa5/PA5.PDF (discussing triangulation, a common method for
determining the location of a radio receiver using three or more signals of known origin and transmission
time).
163. How Does GPS Work?, PHYSICS.ORG, http://www.physics.org/article-questions.asp?id=55 (last
visited Mar. 9, 2016).
164. Introduction to GPS, ESRI, http://webhelp.esri.com/arcpad/8.0/userguide/index.htm#capture_
devices/concept_intro.htm (last visited Mar. 9, 2016).
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Earth using a method called triangulation.165
The waves broadcasted by the GPS satellites are radio waves, which
means that they are a form of light and travel at the speed of light.166 When the
receiver receives a signal, it learns where the satellite is and when it sent the
signal.167 The receiver also includes a clock.168 Therefore, the receiver knows
how long it took the wave from the satellite to arrive at its location.169 A basic
principle of physics is that velocity multiplied by time equals distance.170 The
receiver thus knows that it is somewhere within a certain distance from a
particular location—the location of the satellite when it broadcasts.171 The
receiver repeats the same process twice for waves from two other satellites.172
These calculations give the receiver three intersecting spheres.173 There will
be several points where all three spheres intersect.174 All but one will suggest
that the receiver is far away from Earth’s surface; therefore they can be
discarded.175 The remaining location is the location of the receiver.176
The GPS device does not transmit any information to the satellite in order
to calculate its location; this is done internally on the device.177 The device
that encompasses the GPS receiver, such as a smart phone, has other
capabilities—Wi-Fi, Bluetooth, and radio transmitter to connect to the cell
tower—that can broadcast its location.178
Since there is no requirement of transmitting any signal to the GPS
satellite, the GPS satellite does not store any information regarding how many
devices or the identification of devices in its system.179 Therefore, the only
way to determine the location of a cell phone with a GPS device is if the cell
phone broadcasts its location.
6.
Fiber Optic Tapping
As briefly articulated above, fiber optic cables can be tapped just as easily
as landlines could. Fiber optic cables are coated inside with light reflective
165. STOMBAUGH, supra note 162.
166. XU GUOCHANG, GPS: THEORY, ALGORITHMS AND APPLICATIONS 87 (2d ed. 2007).
167. Id. at 3.
168. Id. at 204.
169. Id. at 3.
170. Speed and Velocity, PHYSICS CLASSROOM, http://www.physicsclassroom.com/class/1DKin/Lesson1/Speed-and-Velocity (last visited Mar. 9, 2016).
171. GUOCHANG, supra note 166.
172. Id. at 108.
173. Id. at 53.
174. Id.
175. Id. at 183
176. Id.
177. Id. at 3.
178. Guy McDowell, How Do Satellites Track Mobile Phones? [Technology Explained], MAKEUSEOF
(Aug. 8, 2009), http://www.makeuseof.com/tag/technology-explained-how-do-satellites-track-mobile-phones/
(illustrating that GPS-enabled phones broadcast their signals in order to be tracked).
179. Cellular vs. Satellite: Understanding the Differences, GLOBAL DATA SYSTEMS (Feb. 24, 2015, 9:42
AM), http://www.getgds.com/blog/cellular-vs.-satellite-understanding-the-differences (explaining that cell
phones use land-based towers and do not communicate with satellites directly).
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material and commonly used to transmit internet flow.180 The light transmits
data at a much higher speed and with less loss in power during transmission.181
Unlike copper wires that have resistance to the electrical current carrying data,
air inside fiber optic cable applies little to no resistance to the light.182 Further,
light has a certain energy level. To ensure that light reaches its destination,
energy used in transmission is higher than necessary.183 A portion of the light
can be redirected from its path without loss of any data transmission.184 The
energy level reaching the destination will be less because some of it is
redirected, but the information will be transmitted regardless.185
Most of the data flowing between ISPs are transferred using fiber optic
cables.186 Fiber optic cables have higher bandwidth, so they can carry more
data than copper cables, which is the type of cable used by the cable
companies.187
7.
Data copying
The easiest way to gather data is by copying. In the common parlance,
when we talk about an e-mail being “sent,” the data that shows the e-mail on
your computer in fact stays in your computer until a copy of it is transmitted
through the communication medium, and then it is deleted from your
computer; nothing physical actually leaves the computer.188 The Internet is a
network of networks. It includes many storage units connected in networks of
storage units, which are connected with other networks creating a massive
world wide web of storage units.189 Internet Exchange Points (“IXP”) are
some of the more centralized locations where Internet traffic flows.190 Some of
the more important IXPs are the ones connecting the United States to Asia and
Europe.191 When IXPs receive data, the data is temporarily stored in the data
180. Physics of Total Internal Reflection, HOWSTUFFWORKS, http://computer.howstuffworks.com/fiberoptic6.htm (last visited Mar. 9, 2016).
181. Miguel Leiva-Gomez, MTE Answers: Why Is Fiber Optic Internet Faster Than Copper?,
MAKETECHEASIER.COM (July 14, 2014), https://www.maketecheasier.com/why-is-fiber-optic-internet-fasterthan-copper/.
182. Id.
183. Introduction to Optical Fibers, dB, Attenuation and Measurements, CISCO, http://www.cisco.com/
c/en/us/support/docs/optical/synchronous-digital-hierarchy-sdh/29000-db-29000.html (noting that excess
energy is lost until fiber reaches equilibrium) (last visited Mar. 9, 2016).
184. Vivek Alwayn, Fiber-Optic Technologies, CISCO (Apr. 23, 2004) http://www.ciscopress.com/
articles/article.asp?p=170740&seqNum=3 (noting that if “the angle of incidence is always equal to the angle of
reflection, the reflected light continues to be reflected.”).
185. CORNING, GET THE FACTS ON OPTICAL FIBER! (2012), http://media.corning.com/flash/opticalfiber/
2012/corning_optical_fiber/Documentation/FIBER_MATTERS/flipbook/585324499/files/inc/585324499.pdf
(last visited Mar. 9, 2016).
186. Id.
187. Id.
188. See Dan Gookin, How E-Mail Works, FOR DUMMIES, http://www.dummies.com/how-to/content/
how-email-works.html (describing, very basically, how e-mail is transferred between recipients) (last visited
Mar. 9, 2016).
189. INT’L TELECOMM. UNION, INTERNET EXCHANGE POINTS (IXPS), (Mar. 2013), https://www.itu.int/
en/wtpf-13/Documents/backgrounder-wtpf-13-ixps-en.pdf.
190. Id.
191. Dennis Weller & Bill Woodcock, Internet Traffic Exchange: Market Developments and Policy
Changes, OECD DIG. ECON. PAPERS (2013), http://www.oecd-ilibrary.org/science-and-technology/ internet-
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center before being sent to another IXP.192 Because of the volume of data
flowing through IXPs, this temporary storage is quickly deleted.193 Yet until it
is deleted, it is susceptible to being copied.194
C.
Data Processing Methods
Any data gathered through a device must be processed one way or
another. A microchip on the digital camera analyzes the electrical signals from
the light sensor in the camera to create the image that was captured.195 The
microchip in the camera can do this very simply because the data incoming
from the sensor is structured.196 This means that there is an order to the
information stream, and it is in a known format.197 Other forms of data
collection may have similar ordered structures making it easy to discern
meaning from them.
The real source of information for law enforcement purposes is the
Internet. As commentators198 and news media199 recognize, much of our
personal information is publicly available online. In a very inspiring and
concerning way, Alessandro Acquisti shares that from a picture of a random
person, you can reach his social security number in two steps using publicly
shared information.200 The major difficulty with the information available on
the Internet is that most of the data is unstructured.201 The unstructured data is
more difficult to analyze because as its name suggests, it does not have a
particular order.202
Yet, big data analytics is a growing field, and it is continuing to improve
the way we view data.203 Also called data mining,204 data processing methods
traffic-exchange_5k918gpt130q-en.
192. GREG PANGRAZIO, SANS INSTITUTE, INTEL IXP NETWORK PROCESSOR BASED INTRUSION
DETECTION (May 22, 2007), https://www.sans.org/reading-room/whitepapers/detection/intel-ixp-networkprocessor-based-intrusion-detection-32919.
193. Id.
194. Id.
195. Kyle
Schurman,
How
Does
a
Digital
Camera
Work?,
GADGET
REV.,
http://www.gadgetreview.com/how-does-a-digital-camera-work (last visited Mar. 9, 2016).
196. See id. (explaining how digital cameras take photographs, digitize them, and create files to view
later).
197. Id.
198. See, e.g., Jose Felipe Anderson, Big Brother or Little Brother? Surrendering Seizure Privacy for the
Benefits of Communication Technology, 81 MISS. L.J. 895, 911 (2012) (“The average citizen has lost so much
control over their personal information that it may be impossible to reverse the trend.”).
199. E.g., Jacob Morgan, Privacy Is Completely and Utterly Dead, and We Killed It, FORBES (Aug. 19,
2014, 12:04 AM), http://www.forbes.com/sites/jacobmorgan/2014/08/19/privacy-is-completely-and-utterlydead-and-we-killed-it/.
200. Alessandra Acquisti, What Will a Future Without Secrets Look Like?, TED (June 2013),
http://www.ted.com/talks/alessandro_acquisti_why_privacy_matters.
201. RONEN FELDMAN & JAMES SANGER, THE TEXT MINING HANDBOOK: ADVANCED APPROACHES IN
ANALYZING UNSTRUCTURED DATA (2006).
202. WILLIAM H. INMON & ANTHONY NESAVICH, TAPPING INTO UNSTRUCTURED DATA: INTEGRATING
UNSTRUCTURED DATA AND TEXTUAL ANALYTICS INTO BUSINESS INTELLIGENCE (2007).
203. See Molly Galetto, Machine Learning and Big Data Analytics: The Perfect Marriage, NG DATA,
http://www.ngdata.com/machine-learning-and-big-data-analytics-the-perfect-marriage/ (last updated Feb. 26,
2016) (describing the field known as “Big Data” and the challenges posed to data analytics).
204. 1 WAYNE R. LAFAVE, SEARCH & SEIZURE § 2.7(e) (5th ed. 2012).
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uncover the secret meaning in seemingly unrelated data.205
One of the most innovative data mining techniques is the use of machine
learning algorithms.206 Traditionally, a computer program would do exactly
what has been programmed, and every step of the analytical rule needed to be
written in the program.207 Machine learning algorithms on the other hand,
generalize analytical rules from examples.208 It saves tremendous amount of
time in data analysis.209
III. BACKGROUND AND ANALYSIS
A.
Text of the Fourth Amendment
The Fourth Amendment of the United States Constitution has its roots,
much like many other parts of the U.S. Constitution, in English traditions
disliked by the colonies.210 Yet, the Fourth Amendment reflects the most
direct attempt to protect against “writs of assistance.”211 These general
warrants allowed officers of the King of England to enter any home and seize
any item that they considered contraband.212
Although the courts in England considered the practice of general
warrants illegal,213 the practice was continued by English authorities in the
colonies to search for evidence of smuggling activities.214
The Fourth Amendment to the United States Constitution states:
The right of the people to be secure in their persons, houses,
papers, and effects, against unreasonable searches and seizures,
shall not be violated, and no Warrants shall issue, but upon
probable cause, supported by Oath or affirmation, and
particularly describing the place to be searched, and the persons
or things to be seized.215
The first half of the Fourth Amendment bans “unreasonable searches and
seizures.”216 The second half, known as the Warrant Clause, prohibits issuance
of warrants without probable cause and requires particularity in its
205. Note, Data Mining, Dog Sniffs, and the Fourth Amendment, 128 HARV. L. REV. 691 (2014).
206. Galetto, supra note 203.
207. Guy M. Haas, Introduction to Computer Programming, BFOIT, http://www.bfoit.org/itp/
Programming.html (last visited Mar. 9, 2016).
208. Pedro Domingos, A Few Useful Things to Know About Machine Learning, 55 COMMS. ACM 78
(Oct. 2012), http://homes.cs.washington.edu/~pedrod/papers/cacm12.pdf.
209. See, e.g., Sneha Agarwal et al., Patci—A Tool for Identifying Scientific Articles Cited by Patents,
GSLIS RESEARCH SHOWCASE (Mar. 14, 2014), https://www.ideals.illinois.edu/handle/2142/54885 (showing a
successful machine learning algorithm to populate fields from unstructured textual data).
210. Thomas K. Clancy, The Framers’ Intent: John Adams, His Era, and the Fourth Amendment, 86
IND. L.J. 979 (2011).
211. Akhil Reed Amar, The Fourth Amendment, Boston, and the Writs of Assistance, 30 SUFFOLK U. L.
REV. 53 (1996).
212. Id.
213. Entick v. Carrington, (1765) 95 Eng. Rep. 807 (K.B.).
214. Annotation 1—Fourth Amendment, FINDLAW, http://constitution.findlaw.com/amendment4/
annotation01.html (last visited Mar. 9, 2016).
215. U.S. CONST. amend. IV.
216. Id.
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description.217
The connection of the Warrant Clause to the Reasonableness Clause has
caused much debate in academia as well as in the Supreme Court.218 The
underlying principle of the Fourth Amendment is a balance of the need for
efficient and effective law enforcement versus the individual’s right to be free
from governmental intrusion.219 It is possible to read the two clauses
separately—one as regulating the reasonableness of searches and seizures, and
the other as regulating the requirements for issuing valid warrants. Therefore,
it imposes increased protection against the intrusion by requiring a
reasonableness requirement for the intrusion in addition to the requirements
imposed on the issuance of a warrant.
Although courts sometimes express a “preference” for warrants and speak
of “exceptions” to the warrant requirement as both traditional220 and
modern,221 current practice is that the exceptions often overwhelm the
preference. The situations where “exceptions” apply are in fact situations
when the interest underlying the Fourth Amendment are implicated to a lesser
extent, such as a reduced expectation of privacy in automobiles,222 or not
implicated at all, such as items left in plain view.223 Another justification for
warrantless searches and seizures is the impracticality of obtaining a warrant in
situations where there is an immediate need to preserve evidence or apprehend
criminals.224 We do not expect a law enforcement officer to stop to obtain a
warrant while chasing a person who has just committed a murder into his or
her house.
The Reasonableness Clause protects the individual’s possessory and
privacy interests. “The touchstone of the Fourth Amendment is
reasonableness . . . .”225 In 1968, the Supreme Court decided Terry v. Ohio.226
In a tremendous leap, the Court recognized that when there is a reduced
intrusion on the liberty of the individual, warrantless searches and seizures can
be effectuated upon reasonable suspicion of the law enforcement officer that a
217. Id.
218. Compare Marron v. United States, 275 U.S. 192 (1927), with Go-Bart Importing Co. v. United
States, 282 U.S. 344 (1931), and United States v. Lefkowitz, 285 U.S. 452 (1932).
219. Silverman v. United States, 365 U.S. 505, 512 (1961).
220. United States v. Robinson, 414 U.S. 218, 224–35 (1973) (holding that searches of a person incident
to a lawful arrest are an exception to the warrant requirement).
221. California v. Acevedo, 500 U.S. 565, 569–70 (1991) (applying an exception to automobile
searches).
222. Id.
223. Washington v. Chrisman, 455 U.S. 1, 5 (1982).
224. With the technological improvements, it is now possible in many states to obtain warrants through
electronic communications. See Missouri v. McNeely, 133 S. Ct. 1552, 1562 n.4 (2013) (holding that the
dissipation of alcohol was not enough to waive the requirement for a warrant for a blood test in a drunk driving
case); 2 WAYNE R. LAFAVE, SEARCH AND SEIZURE § 4.3(c), at 648–54, & 648 n.29 (5th ed. 2012) (describing
oral search warrants and collecting state laws).
225. United States v. Knights, 534 U.S. 112, 118 (2001); see also Illinois v. McArthur, 531 U.S. 326,
330 (2001) (holding that the “central requirement” of the Fourth Amendment “is one of reasonableness”
(internal quotation marks and citation omitted)); Vernonia Sch. Dist. 47J v. Acton, 515 U.S. 646, 652 (1995)
(holding that “[a]s the text of the Fourth Amendment indicates, the ultimate measure of the constitutionality of
a governmental search is ‘reasonableness.’”).
226. Terry v. Ohio, 392 U.S. 1 (1968).
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crime has occurred, or is about to occur.227 In its decision to allow limited—
both in duration and scope—stops and frisks, the Court placed
“reasonableness” at the heart of the Fourth Amendment.228 In Terry, the Court
recognized that a brief detention is justified because the level of intrusion on
the individual’s interest in personal liberty is outweighed by society’s interest
in the investigation of criminal activity.229 Similarly, a pat-down search for
weapons is justified because the safety of a law enforcement officer outweighs
the individual’s interest in privacy when the law enforcement officer has
reasonable suspicion to believe the individual is armed.230 Further, due to
lower intrusion on personal liberty and privacy, the court set the level of
suspicion required to initiate a Terry stop at reasonable suspicion, a degree
lower than probable cause.231
The Warrant Clause, on the other hand, protects the individual by
requiring a neutral judicial officer to review the information available to the
law enforcement officer and determine whether probable cause exists for the
search or seizure.232
The Warrant Clause is a particularly good proxy of what is reasonable,
and the courts have recognized it as such.233 In the situations where a warrant
is not required, if there is probable cause to believe a crime has occurred or
about to occur, the subsequent search or seizure is reasonable.234 The Framers
believed that a warrant particularly describing the place to be searched, or the
item or person to be seized, issued upon a finding of probable cause was a
good balance between law enforcement interests and personal liberty.235
Although the probable cause standard is not difficult to meet, individuals’
interest in privacy of information is balanced against the needs of law
enforcement.236
This loose connection between the Warrant Clause and the
Reasonableness Clause could also mean that some searches or seizures
conducted with a warrant could still be unreasonable.237 Especially when the
amount of information gained through a search is increased further than
traditionally gained through a search of a house, the probable cause standard
227. Id.
228. “For ‘what the Constitution forbids is not all searches and seizures, but unreasonable searches and
seizures.’” Id. at 9 (citing Elkins v. United States, 364 U.S. 206, 222 (1960)).
229. Id.
230. Id.
231. Id
232. George R. Nock, The Point of the Fourth Amendment and the Myth of Magisterial Discretion, 23
CONN. L. REV. 1, 22 (1990).
233. See Akhil Reed Amar, Fourth Amendment First Principles, 107 HARV. L. REV. 757, 782 (1994)
(noting that courts generally attached reasonableness analysis for warrantless searches and seizures); see also
Almeida-Sanchez v. U.S., 413 U.S. 266, 269–72 (1973) (citing examples of courts rationalizing and citing
reasonableness of searches in their cases).
234. Warden, Md. Penitentiary v. Hayden, 387 U.S. 294, 298–300 (1967).
235. See Fabio Arcila, Jr., The Death of Suspicion, 51 WM. & MARY L. REV. 1275, 1275 (2010) (noting
that the Fourth Amendment was a means of limiting governmental search power).
236. See Warden, 387 U.S. at 304 (recognizing that the Fourth Amendment exists to protect one’s
privacy against governmental interests).
237. Id. at 303 (“[T]here are items of evidential value whose very nature precludes them from being the
object of a reasonable search and seizure.”).
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may be insufficient protection under the Reasonableness Clause of the Fourth
Amendment. The Supreme Court alluded to the substantial privacy interests of
data stored in cell phones in Riley v. California.238 While denying law
enforcement officers’ search of cell phones incident to arrest, the Court
recognized that a warrant was available for law enforcement officers to
conduct the search of the cell phone.239 Yet, it also recognized that the amount
of information, both quantitatively and qualitatively, distinguished the search
of a cell phone from the search of a house:
“[A] cell phone search would typically expose to the
government far more than the most exhaustive search of a
house: A phone not only contains in digital form many sensitive
records previously found in the home; it also contains a broad
array of private information never found in a home in any
form—unless the phone is.”240
This stake in an individual’s privacy interest is further complicated in
mass collection of information, which would enable the government to track
the life of a person, not only by what the person himself has done on his phone,
but much more extensively with what others collected about him.241 Until the
recent advancements in technological information, it was not only impractical,
but also impossible to collect the information from so many sources at the
same time and store the information until such time the information is
needed.242 As further discussed below, the privacy interest at stake may leave
a warrant issued upon probable cause unreasonable.
B.
Property v. Privacy
Fourth Amendment protections were initially constructed on top of
property rights.243 The Court in Boyd v. United States244 initially recognized
that foundation in its adaptation of Entick v. Carrington,245 “one of the
landmark [judgments] of English liberty.”246 The Entick court stated that
“every invasion of private property, be it ever so minute, is a trespass.”247
The property-based protection of the Fourth Amendment was reinforced
in Olmstead v. United States.248 In Olmstead, the Court considered whether
wiretapping the defendants’ phones for many months constituted a search or
seizure within the meaning of the Fourth Amendment.249 The Court noted that
“[s]mall wires were inserted along the ordinary telephone wires from the
238.
239.
240.
241.
242.
243.
244.
245.
246.
247.
248.
249.
Riley v. California, 134 S. Ct. 2473, 2493 (2014).
Id. (“Warrant is generally required before such a search.”).
Id.
Id.
Id. at 2489.
Adams v. New York, 192 U.S. 585, 598 (1904); Boyd v. United States, 116 U.S. 616, 627 (1886).
Boyd, 116 U.S. at 627.
Entick v Carrington, (1765) 95 Eng. Rep. 807 (K.B.).
Boyd, 116 U.S. at 626.
Id. at 627.
Olmstead v. United States, 277 U.S. 438, 466 (1928).
Id.
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residences of four of the petitioners and those leading from the chief office”
and “[t]he insertions were made without trespass upon any property of the
defendants.”250 The lack of “an official search and seizure of [defendant’s]
person, or such a seizure of his papers or his tangible material effects, or an
actual physical invasion of his house ‘or curtilage’ for the purpose of making a
seizure” condemned the defendants.251
This property approach was mostly abandoned when the Court decided
Katz v. United States in 1967.252 In Katz, the issue before the Court was
whether listening to a telephone conversation by attaching “an electronic
listening and recording device to the outside of the public telephone booth
from which [the defendant] had placed his calls” was a violation of the Fourth
Amendment.253 The Court has recognized that the “Fourth Amendment
protects people, not places.”254 Further, the Fourth Amendment protects “what
[a person] seeks to preserve as private.”255 The rule created by the majority
was captured in a two-prong test by Justice Harlan in his concurrence.256
Justice Harlan concluded that a search and seizure occurs when a person
displays a subjective expectation of privacy, and when society accepts such
expectation as reasonable. This test carries a first subjective and a second
objective element.
More recently the Court revived the trespass doctrine in United States v.
Jones.257 The issue in Jones was whether GPS tracking of an individual over a
long period of time was a violation of the Fourth Amendment.258 The majority
of the Court avoided the bigger question, whether constant GPS monitoring of
individuals over extended periods of time is reasonable.259 Justice Alito,
writing for himself and three others would have instead applied the Katz test to
find that constant GPS monitoring over extended periods of time is an invasion
of the individual’s privacy interest.260 Justice Sotomayor, writing for herself,
joined the majority in concluding that the Katz test supplements and does not
replace the traditional trespass doctrine.261 Yet, she went on to apply the Katz
test.262
Unlike Justice Alito, Justice Sotomayor would have found that even
short-term GPS monitoring is unreasonable in the absence of a search warrant,
as it tends to show the most intimate details of a person’s life, and therefore it
is a violation of the individual’s privacy interest.263
250.
251.
252.
253.
254.
255.
256.
257.
258.
259.
260.
261.
262.
263.
Id. at 456–57.
Id. at 466.
Katz v. United States, 389 U.S. 347 (1967).
Id. at 348.
Id. at 351.
Id.
Id. at 360–61 (Harlan, J., concurring).
United States v. Jones, 132 S. Ct. 945, 949 (2012).
Id. at 948–49.
Id. at 953–54.
Id. at 963–64 (Alito, J., concurring).
Id. at 955 (Sotomayor, J., concurring).
Id.
Id.
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What is particularly interesting about the two concurring opinions is their
focus on the information obtained from the GPS tracking.264 The comparison
of what law enforcement agencies could accomplish through the use of many
officers, vehicles, and man-hours to the capabilities of technology is a weak
proxy. Traditionally, the protection from long-term surveillance was
practical.265 “Traditional surveillance for any extended period of time was
difficult and costly and therefore rarely undertaken. The surveillance at issue in
[Jones]—constant monitoring of the location of a vehicle for four weeks—
would have required a large team of agents, multiple vehicles, and perhaps
aerial assistance.”266
The protection offered by the Fourth Amendment is centered on the
privacy interest of the individual.267 Therefore, evaluating the privacy interest
at issue in any particular case should be based on the information learned
through surveillance rather than whether it could be obtained through
traditional means.
C.
Search v. Seizure
The majority in Katz did not distinguish the applicability of the test
between searches and seizures.268 Yet, the plain meaning of two words
distinguishes a search from a seizure. A seizure of a person occurs “when the
officer, by means of physical force or show of authority, has in some way
restrained the liberty of a citizen.”269 Similarly, a seizure of property occurs
when there is “some meaningful interference with an individual’s possessory
interests in that property.”270
The literal meaning of a search is best described by the Court in Lopez
v. United States:
In every-day talk, as of 1789 or now, a man ‘searches’ when he
264. Id. at 956 (Sotomayor, J., concurring) (“I would ask whether people reasonably expect that their
movements will be recorded and aggregated in a manner that enables the Government to ascertain, more or
less at will, their political and religious beliefs, sexual habits, and so on.”); id. at 963 (Alito, J., concurring)
(“Recent years have seen the emergence of many new devices that permit the monitoring of a person’s
movements. In some locales, closed-circuit television video monitoring is becoming ubiquitous. On toll roads,
automatic toll collection systems create a precise record of the movements of motorists who choose to make
use of that convenience.”); see also, e.g., People v. Weaver, 909 N.E.2d 1195, 1199–1200, (N.Y. 2009) (noting
that data collected from one’s GPS may disclose information private in nature).
265. Jones, 132 S. Ct. at 963 (Alito, J., concurring).
266. Id.
267. Id. at 954 (Sotomayor, J., concurring).
268. Compare Katz v. United States, 389 U.S. 353 (1967) (“The Government’s activities in
electronically listening to and recording the petitioner’s words violated the privacy upon which he justifiably
relied while using the telephone booth and thus constituted a ‘search and seizure’ within the meaning of the
Fourth Amendment.”) with Jones, 132 S. Ct. at 361 (Harlan, J., concurring) (“[T]he invasion of a
constitutionally protected area by federal authorities is, as the Court has long held, presumptively unreasonable
in the absence of a search warrant.”). However, not much can be read into his choice of “search warrant” as
search warrants commonly authorize seizure of property that is evidence of a crime. See, e.g., WIS. STAT. §
968.13 (2014) (showing that search warrants are generally related to seizure of items that may constitute
evidence of a crime).
269. Terry v. Ohio, 392 U.S. 1, 19 n.16 (1968).
270. United States v. Jacobsen, 466 U.S. 109, 113 (1984); see also LAFAVE, supra note 204, § 2.1(a)
(5th ed. 2012) (noting that the court does not have difficulty defining what constitutes a seizure).
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looks or listens. Thus we find references in the Bible to
‘searching’ the Scriptures (John V, 39); in literature to a man
‘searching’ his heart or conscience; in the law books to
‘searching’ a public record. None of these acts requires a manual
rummaging for concealed objects. . . . Just as looking around a
room is searching, listening to the sounds in a room is searching.
Seeing and hearing are both reactions of a human being to the
physical environment around him—to light waves in one
instance, to sound waves in the other. And, accordingly, using a
mechanical aid to either seeing or hearing is also a form of
searching. The camera and the dictaphone both do the work of
the end-organs of an individual human searcher—more
accurately.271
In the abstract, communication, whether through the Internet or over the
phone, is difficult to fit within the categories of search or seizure.272 Yet,
technological realities, when analogized to traditional definitions, sheds light
on how to categorize the access to information. As explained above,273 most
information is obtained without a physical intrusion.274
The literal meaning of a search, “to carefully look for someone or
something[;] to try to find someone or something,”275 is well established. Until
recently there was no need to distinguish between collection and access of
information because in many instances, the collection of data by the agency
(for example wiretapping) and access to that information (listening to the
wiretapped conversation) was simultaneous. Further, the scope of data
collected and analyzed by government agencies was beyond the technological
capabilities of human development.
D.
Government’s Subjective Intent
The Court has generally treated subjective intent of the law enforcement
officer as irrelevant to the Fourth Amendment analysis. The Court never held
“that an officer’s motive invalidates objectively justifiable behavior under the
Fourth Amendment; but [the Court] ha[s] repeatedly held and asserted the
contrary.”276 Inventory searches277 and administrative inspections278 are the
271. Lopez v. United States, 373 U.S. 427, 459 (1963) (Brennan, J., dissenting) (quoting United States v.
On Lee, 193 F.2d 306, 313 (2d. Cir. 1951) (Frank, J., dissenting)); see also LAFAVE, supra note 204, § 2.1(a)
(5th ed. 2012) (defining search under the traditional approach).
272. See CLIFFORD S. FISHMAN & ANNA T. MCKENNA, WIRETAPPING AND EAVESDROPPING § 1:5 (2015)
(noting fundamental difficulty in distinguishing between a search for a conversation and a seizure of said
conversation).
273. Jones, 132 S. Ct. at 955 (Sotomayor, J., concurring).
274. Id.
275. See MERRIAM-WEBSTER ONLINE DICTIONARY (2015), http://www.merriam-webster.com/dictionary/
search (last visited Mar. 9, 2016) (providing the definition of “search”).
276. Whren v. United States, 517 U.S. 806, 812 (1996).
277. An inventory search is the search of property lawfully seized and detained in order to ensure that it
is harmless, to secure valuable items (such as might be kept in a towed car), and to protect against false claims
of loss or damage. See South Dakota v. Opperman, 428 U.S. 364, 369 (1976) (discussing further how different
jurisdictions handle inventory searches).
278. An administrative inspection is the inspection of business premises conducted by authorities
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exceptions to this general rule. When government officials conduct inventory
searches or administrative inspections as a pretext to discovering incriminating
evidence without probable cause, they violate the Fourth Amendment.279
Yet, the subjective intent of government officials may sometimes be
relevant to the objectiveness analysis. In Florida v. Jardines,280 the Court
considered a case where police officers approached the front door of a house—
an area also considered curtilage281—without a warrant with a drug-sniffing
dog to investigate an unverified tip282 that marijuana was being grown in the
house.283 The Court decided the case based on the property-based protection
of the Fourth Amendment.284 The Court first recognized that there was an
“implied license” for the public to come into the curtilage to knock on the
door.285 Yet, “[t]he scope of [this] license—express or implied—is limited not
only to a particular area but also to a specific purpose.”286 The Court held that
introducing “a trained police dog to explore the area around the home in hopes
of discovering incriminating evidence” was not within that implied license to
enter the curtilage.287 Consequently, the officers were trespassing into an area
protected by the Fourth Amendment when they entered into the curtilage for
the purpose of obtaining incriminating evidence.288 Therefore, this act of
trespass was a search within the meaning of the Fourth Amendment.289
The violation in Florida v. Jardines did not occur by the simple act of
entering the curtilage; the violation occurred because police officers entered
the curtilage “to engage in conduct not explicitly or implicitly permitted by the
homeowner.”290 The Court stated: “no one is impliedly invited to enter the
protected premises of the home in order to do nothing but conduct a search.”291
Although this language seems to inject the subjective purpose of the
government official engaging in a particular conduct into the Fourth
responsible for enforcing a pervasive regulatory scheme—for example, unannounced inspection of a mine for
compliance with health and safety standards. See Donovan v. Dewey, 452 U.S. 594, 599–605 (1981)
(discussing how different jurisdictions have handled administrative inspections).
279. See Opperman, 428 U.S. at 379 (discussing pretextual inventory searches).
280. Florida v. Jardines, 133 S. Ct. 1409, 1416 (2013).
281. Curtilage is defined as the area “immediately surrounding and associated with the home,” which is
considered as “part of the home itself for Fourth Amendment purposes.” Oliver v. United States, 466 U.S. 170,
176 (1984). Further, this area around the home is “intimately linked to the home, both physically and
psychologically,” and is where “privacy expectations are most heightened.” California v. Ciraolo, 476 U.S.
207, 213 (1986).
282. An “unverified tip” is usually not enough for a finding of probable cause. Adams v. Williams, 407
U.S. 143, 147 (1972) (“Some tips, completely lacking in indicia of reliability, would either warrant no police
response or require further investigation before a forcible stop of a suspect would be authorized.”).
283. Jardines, 133 S. Ct. at 1413.
284. “[T]hough Katz may add to the baseline, it does not subtract anything from the Amendment’s
protections ‘when the Government does engage in [a] physical intrusion of a constitutionally protected area.’”
Id. at 1414 (citing United States v. Knotts, 460 U.S. 276, 286 (1983) (Brennan, J., concurring in the
judgment)).
285. Id.
286. Id. at 1416.
287. Id.
288. Id.
289. Id.
290. Id. at 1414.
291. Id. at 1416 n.4.
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Amendment analysis, it is likely to be limited to the context of property-based
(trespass) Fourth Amendment analyses.
Further, the lack of a purpose analysis in determining whether a violation
has occurred exists in other contexts as well. In Smith v. Maryland,292 the
Court concluded that “because individuals have no actual or legitimate
expectation of privacy in information they voluntarily relinquish to telephone
companies, the use of pen registers by government agents is immune from
Fourth Amendment scrutiny.”293 The Court did not distinguish between the
purposes of revealing information to the telephone companies. According to
Justice Marshall, though, writing for the dissent, “[p]rivacy is not a discrete
commodity, possessed absolutely or not at all. Those who disclose certain
facts to a bank or phone company for a limited business purpose need not
assume that this information will be released to other persons for other
purposes.”294
The irrelevancy of subjective intent is important because data collection
and analysis is a tremendously powerful tool in law enforcement. Although
local law enforcement agencies do not yet have the technical capabilities to
intercept entire sets of data communications, the improvement in technology
already allows them to process high amounts of data in a fraction of a
second.295 Royal Canadian Mounted Police (“RCMP”) uses automatic license
plate recognition technology to monitor vehicles on the road for unregistered
vehicles and other criminal associations.296 The statistics published on the
RCMP’s website reveal that in two years over three million license plates have
been scanned, and over sixty thousand license plates have been flagged for one
reason or another.297
E.
Expectation of Privacy
Following the Supreme Court’s landmark decision in Katz v. United
States, a “search” has been understood to mean an activity that intrudes upon a
citizen’s “constitutionally protected reasonable expectation of privacy.”298 As
articulated in Justice Harlan’s concurrence, a person must exhibit a subjective
expectation of privacy, and that expectation must be reasonable in the public’s
eye.299
Later courts have somewhat dialed back on the role of subjective
292.
293.
294.
295.
Smith v. Maryland, 442 U.S. 735, 749 (1979) (Marshall, J., dissenting).
Id.
Id.
See, e.g., Tres Watkins, Data Mining the Criminal Mind: Big Data and Law Enforcement,
SYNCFUSION (Aug. 15, 2014), https://www.syncfusion.com/blogs/post/Data-Mining-the-Criminal-Mind-BigData-and-Law-Enforcement.aspx (discussing various types of technologies available to law enforcement).
296. Automatic License Plate Recognition Technology, ROYAL CANADIAN MOUNTED POLICE,
http://traffic.rcmp-grc.gc.ca/ViewPage.action?siteNodeId=23&languageId=1&contentId=11953 (last visited
Mar. 6, 2016) (“The [Automatic License Plate Recognition] System is a license plate recognition program that
allows vehicles observed by cameras to have their license plate read and recorded using pattern recognition
software.”).
297. Id.
298. Katz v. United States, 389 U.S. 347, 360 (Harlan, J., concurring).
299. Id.; LAFAVE, supra note 204, § 2.1 (c)
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expectation of privacy as a requirement for Fourth Amendment protection.300
It is very easy to destroy a person’s subjective expectation of privacy from a
position of power. This is most evident in airports where the expectation of
privacy is none because of many postings around the airport telling people that
they don’t have an expectation of privacy.301
People’s online presence and the tendency to share information regarding
their daily lives can also be an indication of a reduced subjective expectation of
privacy. Many websites inform users that they collect and analyze usage data
or other information regarding the user.302 Even the collection of the data by
the government of this data raises eyebrows.303 In this respect, the problem is
how to answer the question “expectation of privacy in what?”304 The answer is
quite simply “information”—information regarding our activities, thoughts,
associations, or “what hour each night the lady of the house takes her daily
sauna and bath.”305
In Kyllo v. United States, the Court, in considering the Fourth
Amendment implications of thermal imagers, drew a bright line rule that
thermal imagers, which had the capabilities to reveal intimate details of the
home, could not be used to conduct a search without a warrant.306 The Court
rejected the government’s argument that the thermal imager in this instance did
not “detect private activities occurring in private areas,” and stated that “[t]he
Fourth Amendment’s protection of the home has never been tied to the
measurement of the quality or quantity of information obtained.”307 What the
Court was concerned with was the potential of the thermal imager to obtain
such information.308
In this respect, two proxies regarding expectation of privacy are relevant
to our issue: knowing exposure to the public309 and devices in general public
use.310
300. LAFAVE, supra note 204, § 2.1 (c).
301. Julie Solomon, Does the TSA Have Stage Fright? Then Why Are They Picturing You Naked?, 73 J.
AIR L. & COM. 643, 645–46 (2008).
302. See, e.g., Data Policy, FACEBOOK, https://www.facebook.com/about/privacy (last visited Mar. 9,
2016) (describing Facebook’s utilization of user data); Welcome to the Google Privacy Policy, GOOGLE,
https://www.google.com/intl/en/policies/privacy/ (last visited Mar. 9, 2016) (describing Google’s utilization of
user data); Yahoo Privacy Center, YAHOO!, https://policies.yahoo.com/us/en/yahoo/privacy/index.htm (last
visited Mar. 9, 2016) (describing Yahoo’s utilization of user data).
303. Mike Gentithes, When the Government Mines “Big Data,” Does It Conduct a Fourth Amendment
Search?, CBA RECORD, Jan. 2015, at 36, 38 (“While minor government harassment that disturbs a single
citizen’s tranquility may be trivial and fail to reach the level of a Fourth Amendment search, it is still a greaterthan-zero intrusion upon our collective tranquility interest that, when accumulated in a program as broad as the
NSA’s, may be sufficient to constitute a search and trigger the Fourth Amendment’s protections.”).
304. Orin S. Kerr, The Mosaic Theory of the Fourth Amendment, 111 MICH. L. REV. 311 (2012); see also
LAFAVE, supra note 204, § 2.7(e) (“Perhaps the best that can be done in this brief treatment of the subject is to
identify more clearly what legitimate privacy concerns attend the investigative processes here under
discussion.”).
305. Kyllo v. United States, 533 U.S. 27, 38 (2001).
306. Id.
307. Id.
308. Id.
309. California v. Ciraolo, 476 U.S. 207, 213 (1986).
310. Kyllo, 533 U.S. at 29.
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Knowing Exposure to the Public
“What a person knowingly exposes to the public, even in his own home
or office, is not a subject of Fourth Amendment protection.”311 The idea
behind knowing exposure to the public is the expectation of privacy.312 There
is no expectation of privacy on what a person reveals to the public.313 This
may explain treating light differently based on its wavelength. Visible light
only passes through windows and the police can see through it. So, if the
person does not have drapes, whatever is visible inside has no Fourth
Amendment implications. With regard to thermal imaging, however, the
infrared light emitted from the heat sources inside the house—such as people,
hot showers, and heat lamps—are exposed without intention.314
The trouble with this standard is twofold. First, this destroys any Fourth
Amendment protection to digital data. In Smith v. Maryland, the Court held
that a person does not have an expectation of privacy in information disclosed
voluntarily to a third party, such as the telephone company, including the
numbers dialed.315 Similarly, most browsing data and other information
transferred on a computer travels through data centers and is in many ways
exposed to a third party.316
The second trouble is the mental state of knowing.317 This should be
taken more strictly and more akin to intentional because even though we know
everything that has heat in it will emanate in the form of infrared light, it is not
necessarily true that we intend to expose the heat from the shower to others.318
Concerning online presence, it is simply too difficult to expect any kind
of right to privacy. However, the question is not whether we display an
expectation of privacy in each individual piece of information we enter on the
Internet, but whether an expectation of privacy exists in all of our activities and
preferences. The information gained from one’s browsing history is simply far
more useful and more potent than a search of the home.
In the online context, it is possible to create a very secure connection with
an online server using a HTTPS protocol, which uses a two-layer
communication protocol that encrypts data during transfer.319 Yet, most
websites do not offer HTTPS support, and it is not possible to unilaterally set
up such a connection from the user’s end.320 Regardless of the secure
connection, it is still a secure connection to a third party, from whom the
311. Katz v. United States, 389 U.S. 347, 351 (1967).
312. Id. at 361 (Harlan, J., concurring).
313. Id.
314. Kyllo, 533 U.S. at 27, 35.
315. Smith v. Maryland, 442 U.S. 735 (1979).
316. Rus Shuler, How Does the Internet Work?, STANFORD (2002), https://web.stanford.edu/class/
msande91si/www-spr04/readings/week1/InternetWhitepaper.htm.
317. Katz v. United States, 389 U.S. 347, 351 (1967).
318. See Kyllo, 533 U.S. at 33 (discussing the importance of a subjective expectation of privacy).
319. What is HTTPS?, INSTANT SSL BY COMODO, https://www.instantssl.com/ssl-certificateproducts/https.html (last visited Mar. 9, 2016).
320. Scott Gilbertson, HTTPS Is More Secure, So Why Isn’t the Web Using It?, ARS TECHNICA (Mar. 20,
2011, 6:00 PM), http://arstechnica.com/business/2011/03/https-is-more-secure-so-why-isnt-the-web-using-it/.
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government can obtain the information without running afoul of the Fourth
Amendment.321
Finally, what is it that is “knowingly exposed to the public?”322 Is it a
particular piece of fact, or is it the information that several particular pieces of
fact can tell about that person? With online data, each piece of information, a
data point, may not be meaningful in any sense, but in aggregation as a data
set, it does become meaningful and a meaning that the person never intended
to reveal or never knew could be revealed.323
2.
Devices in General Public Use
The Supreme Court developed “devices in general public use” as another
proxy to determine the reasonable expectation of privacy in Kyllo v. United
States.324 In Kyllo, the police officers “suspect[ed] that marijuana was being
grown in the home belonging to petitioner” and used a thermal imager to scan
the home.325
Thermal imaging devices detect infrared light in the
electromagnetic spectrum.326 The light visible to the human eye has
wavelengths between 390 nanometers and 700 nanometers.327 Infrared light
has a wavelength greater than 700 nanometers and less than one millimeter
(one million nanometers).328 Therefore, infrared light cannot be seen by the
naked eye without help.329 The Court held that, when “the technology in
question is not in general public use . . . obtaining by sense-enhancing
technology any information regarding the interior of the home that could not
otherwise have been obtained without physical intrusion into a constitutionally
protected area, constitutes a search.”330 The Court used the “general public
use” as a proxy for the expectation of privacy.331
As highlighted by the dissent in Kyllo, “the contours of [the Court’s] new
rule are uncertain because its protection apparently dissipates as soon as the
relevant technology is ‘in general public use.’”332 The earliest patent on the
method for creating thermal imagers was filed as early as 1946.333 Yet, the
321. Jennifer Valentino-Devries, How Technology Is Testing the Fourth Amendment, DIGITS (Sept. 21,
2011, 10:32 PM), http://blogs.wsj.com/digits/2011/09/21/how-technology-is-testing-the-fourth-amendment/.
322. Katz, 389 U.S. at 351 (1967).
323. Laura Lenhart, Personal Information, Personal Property, ILL. DIGITAL ENV’T FOR ACCESS TO
LEARNING & SCHOLARSHIP, https://www.ideals.illinois.edu/bitstream/handle/2142/42118/454e.pdf (last visited
Mar. 6, 2016).
324. Kyllo v. U.S., 533 U.S. 27 (2001).
325. Id. at 34.
326. How Thermal Imaging Works, INFO.COM, http://topics.info.com/How-Thermal-Imaging-Works_
1502 (last visited Mar. 9, 2016).
327. Christopher Crockett, What Is the Electromagnetic Spectrum?, EARTHSKY (May 19, 2014),
http://earthsky.org/space/what-is-the-electromagnetic-spectrum.
328. Jim Lucas, What Is Infrared?, LIVE SCI. (Mar. 26, 2015, 2:52 AM) http://www.livescience.com/
50260-infrared-radiation.html.
329. Id.
330. Kyllo, 533 U.S. at 3 (quoting Silverman v. U.S., 365 U.S. 505, 512 (1961))
331. Id. (“This assures preservation of that degree of privacy against government that existed when the
Fourth Amendment was adopted.”).
332. Id. at 47 (Stevens, J., dissenting).
333. U.S. Patent No. 2,403,066 (filed Dec. 28, 1943).
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first thermal imagers were introduced in 1960s.334 Until the 1990s, however,
the cost of producing thermal imagers outweighed the benefit.335 When the
court decided the case in 2001, the cost of thermal imagers were still relatively
high.336 Now, fifteen years after the Kyllo decision, a thermal imager for an
iPhone can be purchased for $250.337 Thermal imagers are also used
frequently by homeowners to detect parts of the house that leak heat and are in
need of insulation.338
F.
Wiretapping
Wiretapping is a highly regulated area. The Federal Wiretap Act makes it
a criminal offense to intercept communications traveling on interstate or
foreign commerce.339 In Berger v. State of New York, the Court held
“‘conversation’ [is] within the Fourth Amendment’s protections, and that the
use of electronic devices to capture it [is] a ‘search’ within the meaning of the
Amendment . . . .”340 Mass data collection by the National Security Agency
(“NSA”) reported by the news341 and acknowledged by the Obama
administration342 has drawn much interest by the public343 as well as
academics.344
G.
Mosaic Theory
Recent literature has focused on the idea of a “mosaic theory” of the
Fourth Amendment.345 The D.C. Circuit in United States v. Maynard
introduced the mosaic theory.346
“Under the mosaic theory, searches can be analyzed as a
334. History of Thermal Imaging, BULLARD, www.bullard.com/V3/products/thermal_imaging/
history_of_thermal_imaging.php (last visited Mar. 9, 2016).
335. FLIR, THE THERMAL REVOLUTION (June 2007), http://www.flir.com/uploadedFiles/CVS_Americas/
Security/Applications/App_Notes_Revolution_a.pdf.
336. Id.
337. Buy FLIR ONE, FLIR, http://www.flir.com/flirone/display/?id=69324 (last visited Mar. 9, 2016).
338. Thermal Imaging Cameras Explained, GRAINGER, https://www.grainger.com/content/qt-thermalimaging-applications-uses-features-345 (last updated Sept. 2015).
339. 18 U.S.C. § 2511 (2012).
340. 388 U.S. 41, 51 (1967).
341. Glenn Greenwald, NSA Collecting Phone Records of Millions of Verizon Customers Daily,
GUARDIAN (June 6, 2013, 6:05 AM), http://www.theguardian.com/world/2013/jun/06/nsa-phone-recordsverizon-court-order.
342. Roberts & Ackerman, supra note 17.
343. Susan Page, Poll: Most Americans Now Oppose the NSA Program, USA TODAY (Jan. 20, 2014,
3:10 PM), http://www.usatoday.com/story/news/politics/2014/01/20/poll-nsa-surveillance/4638551/.
344. See, e.g., Blake Covington Norvell, The Constitution and the NSA Warrantless Wiretapping
Program: A Fourth Amendment Violation?, 11 YALE J. L. & TECH. 228 (2009) (discussing the constitutionality
of the NSA’s wiretapping program).
345. David C. Gray & Danielle Keats Citron, A Shattered Looking Glass: The Pitfalls and Potential of
the Mosaic Theory of Fourth Amendment Privacy, 14 N.C.J.L. & TECH. 381 (2013); Orin S. Kerr, The Mosaic
Theory of the Fourth Amendment, 111 MICH. L. REV. 311 (2012); Priscilla J. Smith, Much Ado About
Mosaics: How Original Principles Apply to Evolving Technology in United States v. Jones, 14 N.C.J.L. &
TECH. 557 (2013).
346. 615 F.3d 544, 562 (D.C. Cir. 2015).
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collective sequence of steps rather than as individual steps.”347
Identifying Fourth Amendment searches requires analyzing
police actions over time as a collective “mosaic” of
surveillance; the mosaic can count as a collective Fourth
Amendment search even though the individual steps taken in
isolation do not.”348
The Supreme Court took the appeal from United States v. Maynard and
analyzed the case under the Fourth Amendment.349 The Court was divided in
United States v. Jones.350 Justice Scalia, writing for the Court, decided the
case under the trespass doctrine.351 Justice Alito, joined by three other justices,
would have decided the case under the reasonable expectation of privacy
analysis.352 According to Justice Alito, “[s]hort-term monitoring of a person’s
movements on public streets accords with expectations of privacy” but “the use
of longer term GPS monitoring in investigations of most offenses impinges on
expectations of privacy.”353 As the Maynard court explained:
Prolonged surveillance reveals types of information not revealed by
short-term surveillance, such as what a person does repeatedly, what
he does not do, and what he does ensemble. These types of
information can each reveal more about a person than does any
individual trip viewed in isolation. Repeated visits to a church, a
gym, a bar, or a bookie tell a story not told by any single visit, as
does one’s not visiting any of these places over the course of a
month. The sequence of a person’s movements can reveal still
more; a single trip to a gynecologist’s office tells little about a
woman, but that trip followed a few weeks later by a visit to a baby
supply store tells a different story. A person who knows all of
another’s travels can deduce whether he is a weekly church goer, a
heavy drinker, a regular at the gym, an unfaithful husband, an
outpatient receiving medical treatment, an associate of particular
individuals or political groups—and not just one such fact about a
person, but all such facts.354
Justice Sotomayor, alone in her concurring opinion, joined Justice
Scalia’s opinion with regard to the application of the trespass doctrine.355 Yet,
she went further than Justice Alito’s opinion with regard to the reasonable
expectation of privacy analysis and explained that even short-term GPS
monitoring would violate the Fourth Amendment under a reasonable
expectation of privacy analysis.356
In order to give more context to the mosaic theory, it might be beneficial
347.
348.
349.
350.
351.
352.
353.
354.
355.
356.
Id.
Kerr, supra note 345, at 313.
United States v. Jones, 132 S. Ct. 945 (2012).
Id. at 952.
Id. at 948.
Id. at 957–64.
Id. at 964.
United States v. Maynard, 615 F.3d 544, 562 (D.C. Cir. 2010).
Jones, 132 S. Ct. at 954–57.
Id. at 955.
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to look at the factual scenario that occurred in United States v. Jones. In Jones,
law enforcement officers installed a GPS device under the defendant’s car to
monitor his movements in public roads over four weeks.357 At any individual
point in time, because the defendant “knowingly exposes [his location] to the
public,”358 no search occurs. However, when an individual’s movements on
public roads are monitored for four weeks, the mosaic theory would hold that a
search occurs because of the collective actions by the law enforcement
officers.359
Further, there remains a question of whether individual pieces of
information that do not reveal any information can become protected by the
Fourth Amendment by nature of its aggregation.360
The mosaic theory, however, mischaracterizes when a search occurs. It is
very different to say that a search does not occur when a person is viewed in a
public street and when a person is followed through a GPS device for a period
of time. The information gained through one is very different than the
information gained through the other.361 The mosaic theory “groups conduct
that is not a search and asks if the non-searches considered together cross the
line to become a search.”362 This approach presupposes that a reasonable
expectation of privacy can only be in the place to be searched or the item to be
seized. There are three versions of mosaic theory that outline a reasonable
expectation of privacy: “societal expectations about law enforcement
practices,” “government power,” and “whether the government learned more
than a stranger could have observed.”363 All of these standards suffer from
ambiguity on how to determine the society’s knowledge or expectations of
what others might do.364
However, the focus of both Justices of the Supreme Court and
commentators is on what information is learned.365 What is learned from a
brief encounter on the street and constant surveillance is easily
distinguishable.366 The Fourth Amendment’s protection does not depend on
“measurement of the quality or quantity of information obtained”367 by the
government’s surveillance technique, but what that technique has the potential
357. Id. at 963.
358. Maynard, 615 F.3d at 559.
359. Jones, 132 S. Ct. at 964.
360. Joseph S. Fulda, Data Mining and Privacy, 11 ALB. L.J. SCI. & TECH. 105, 109 (2000) (“Is it
possible for data that does not in itself deserve legal protection to contain implicit knowledge that does deserve
legal protection?”).
361. Maynard, 615 F.3d at 556.
362. Kerr, supra note 345, at 329.
363. Id. at 350.
364. See id. (discussing in further detail how standards suffer).
365. See Matthew B. Kugler & Lior Strahilovitz, Surveillance Durations Doesn’t Affect Privacy
Expectations: An Empirical Test of the Mosaic Theory 5 (Univ. of Chi. Law Sch., Working Paper No. 727,
2015) (discussing the Supreme Court’s focus on the types of information captured via extended surveillance
and academic analysis thereof).
366. See id. at 36 (stating the stark differences between information obtained via lengthy surveillance
and that obtained via brief tracking).
367. Kyllo v. United States, 533 U.S. 27, 37 (2001).
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to reveal.368
H.
Section 215 of the USA PATRIOT Act
Section 215 of the USA PATRIOT Act was interpreted by the NSA to
allow access to personally identifiable information upon “a statement of facts
showing that there are reasonable grounds to believe that the tangible objects
sought are relevant . . . against international terrorism . . . .”369 The NSA has
created a program to collect and store telephone metadata through private
phone companies such as Verizon Wireless.370 The NSA’s program was
authorized by Section 215 of the USA PATRIOT Act.371 It also allowed the
government to compel the production of “any tangible things (including books,
records, papers, documents, and other items).”372 It is regarded as one of the
most expensive pieces of legislation authorizing government activity, and even
the drafter of the act does not support that reading of the statute.373
IV. ANALYSIS
From the review of the case law and commentators it is evident that the
activities of the government run afoul of the Fourth Amendment when those
activities have potential to reveal information in excess of what the
government could traditionally learn without warrants.374 The highest
protection of the Fourth Amendment is at home375 because of the information
contained inside the four corners of the home and blocked by the walls.376
These intimate details are what separate the home from other places, and these
intimate details are what the Fourth Amendment ought to protect.
A.
Reasonable Expectation of Privacy in Life
One of the biggest difficulties in scrutinizing the collection and analysis
368. See id. at 38 (discussing what information is revealed by the use of a thermal imaging device and
the circumscriptions on the information as contemplated by the Fourth Amendment).
369. USA PATRIOT Improvement and Reauthorization Act of 2005, 50 U.S.C. § 1861(b)(2)(B) (2012).
370. For a detailed discussion of phone metadata collection and related Supreme Court jurisprudence,
see Nathaniel Wackman, Historical Cellular Location Information and the Fourth Amendment, 2015 U. Ill. L.
Rev. 263 (2015), which provides a detailed discussion of phone metadata collection and related Supreme Court
jurisprudence. For a discussion of the challenge against NSA program, see Susan Freiwald, Nothing to Fear
or Nowhere to Hide: Competing Visions of the NSA’s 215 Program, 12 COLO. TECH. L.J. 309, 323 (2014),
which discusses the challenges against the NSA’s surveillance programs.
371. 50 U.S.C. § 1861(c)(2)(F)(iv).
372. 50 U.S.C. § 1861(a)(1).
373. Sensenbrenner: PATRIOT Act Needs Changes After NSA Revelations, WISPOLITICS.COM, (June
24, 2013 9:26 AM), http://dc.wispolitics.com/2013/06/sensenbrenner-patriot-act-needs-changes.html (“[NSA
activities leaked by Edward Snowden] certainly was not what was contemplated when the PATRIOT Act was
passed.”).
374. See generally id. (revealing Rep. Sensenbrenner’s belief that Snowden’s releasing classified
information showed the public that the law was being used in ways that were unintended in the original
debate).
375. Kyllo v. United States, 533 U.S. 27, 40 (2001) (citing Payton v. New York, 445 U.S. 573, 590
(1980)).
376. Id.
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of data by the government is the knowing exposure of this information to third
parties.377 Most of the data exchanged over the Internet is necessarily shared
with ISPs and at least the information that you are trying to receive is
shared.378 This particular limitation defeats the Fourth Amendment protection
just because of how the Internet is set up.
The acts and communications displayed in the virtual environment
through our use of technology to track our lives would suggest that people do
not have that expectation of privacy. In a more traditional approach to the
Fourth Amendment, our individual acts of revealing certain information to
third parties, as articulated above, suggests that there is no expectation of
privacy. Even then, however, no one in 1776 would have expected that when
he or she shares certain information with certain people, those people would
get together and share their knowledge. It would be unreasonable to expect
people to do so. A person in 1776 would have a privacy interest in the
aggregated information, because aggregated information is our lives.
At least one circuit court has already articulated this position in Reeves v.
Churchich.379 The court held that pointing a rifle at a premises occupant, even
if the end of the rifle was inserted inside those premises and “constituted a
common law trespass,” nonetheless was “not a Fourth Amendment violation”
because “the rifle was incapable of obtaining information.”380 The outcome of
Reeves might be different in light of Jones v. United States, however, where
the Court reviewed the technical trespass further381 and reflected the premise
that the privacy is in the information and not simply how it is obtained.382
Further, the courts have already considered technological devices that
gather certain information and characterized the use of such devices as a
search.383 In United States v. Epperson, in concluding that the use of a
magnetometer was a search, the court stated, “a government officer, without
permission, discerned metal on Epperson’s person.”384 These increased
technologies do not simply “enhance police senses as they do replace them
with something superhuman, an ability to perceive that people simply do not
have.”385 These devices give new information to the officer—information they
377. Katz v. United States, 389 U.S. 347, 351 (1967).
378. See Rory Cellan-Jones, Web Surveillance—Who’s Got Your Data?, BBC NEWS (Apr. 2, 2012),
http://www.bbc.com/news/technology-17586605 (articulating the position that while ISPs may not collect
personally identifiable information, they are collecting metadata on their users).
379. Reeves v. Churchich, 484 F.3d 1244 (10th Cir. 2007).
380. Id. at 1256.
381. See United States v. Jones, 132 S. Ct. 945, 951 n.5 (2012) (discussing the general principle that a
trespass must be conjoined with an attempt to gain information to constitute a search).
382. See Reeves, 484 F.3d 1244 (illustrating that the right to privacy and protection against unlawful
searches attaches to specific information sought to be kept private and not simply the means by which law
enforcement might search).
383. See LAFAVE, supra note 204 (elaborating on the impact of the expansion of technology and court
opinions that have limited such technology being used to conduct surveillance on American citizens).
384. United States v. Epperson, 454 F.2d 769, 770 (4th Cir. 1972).
385. David A. Harris, Superman’s X-Ray Vision and the Fourth Amendment: The New Gun Detection
Technology, 69 TEMP. L. REV. 1, 24 (1996) (emphasis added); see also Christopher Slobogin, TechnologicallyAssisted Physical Surveillance: The American Bar Association’s Tentative Draft Standards, 10 HARV. J.L. &
TECH. 383, 447–52 (1997) (reaching same conclusion and discussing proposed limitations on use of such
devices).
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could not otherwise obtain or gather.386
In describing “the right to be let alone” Justice Brandeis, in his dissenting
opinion in Olmstead v. United States, stated the Framers “sought to protect
Americans in their beliefs, their thoughts, their emotions and their
sensations.387 They conferred, as against the government, the right to be let
alone—the most comprehensive of rights and the right most valued by
civilized men.”388 Although the Fourth Amendment does not give “a general
constitutional ‘right to privacy,’”389 it does protect “what he [or she] seeks to
preserve as private, even in an area accessible to the public.”390 What he or she
seeks to preserve as private is information about himself or herself—thoughts,
beliefs, and browsing history.391 After all, “the Fourth Amendment protects
people, not places.”392
Imagine that a police officer is standing in a pitch-dark room, and there is
nothing in his reaching distance.393 Standing there in the room, the officer
cannot learn anything. He can try to look for things but his capability to do so
is limited by his eyes. Because there is no information gained, no search
occurs.
B.
Information Gathering is Not Seizure
Information gathering is not seizure because there is no “meaningful
interference with an individual’s possessory interests in” information.394 First,
as discussed above, “[d]ata in its ethereal, non-physical form is simply
information . . . .”395 It is difficult to conceptualize how one can seize
information. It is possible to seize items containing information, such as
papers or hard drives, but information itself is not seized. Second of all,
although there is a privacy interest in information, it does not translate to a
possessory interest.396 Finally, there is no meaningful interference with the
flow of information. Just as in Katz, the information continues to flow and it is
copied rather than intercepted.397
Yet, data gathering, even without the analysis, can have a substantial
386. See Slobogin, supra note 385, at 385 (discussing some of the general applications of surveillance
technology in law enforcement).
387. Olmstead v. United States, 277 U.S. 438, 478 (1928) (Brandeis, J., dissenting).
388. Id.
389. Katz v. United States, 389 U.S. 347, 350 (1967).
390. Id. at 351.
391. See generally Nathan Freed Wessler, How Private Is Your Online Search History?, AM. C.L. UNION
(Nov. 12, 2013, 12:04 PM), http://www.aclu.org/blog/how-private-your-online-search-history (exploring the
privacy of web browser and Internet search history).
392. Katz, 389 U.S. at 351.
393. For the purposes of this example assume there is no trespass.
394. United States v. Jacobsen, 466 U.S. 109, 113 (1984).
395. Digitech Image Techs., LLC v. Elecs. for Imaging, Inc., 758 F.3d 1344, 1350 (Fed. Cir. 2014).
396. See Steven G. Davison, Warrantless Investigative Seizures of Real and Tangible Personal Property
by Law Enforcement Officers, 25 AM. CRIM. L. REV. 577, 599 (1988) (highlighting the distinction between
“possessory interests” and “privacy interests” in the context of searches and seizures under the Fourth
Amendment).
397. As discussed above in Part II, some of the techniques do allow for interception of the data and such
techniques may implicate the Fourth Amendment. This point is outside the scope of this project.
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chilling effect on peoples’ activities. Knowing that every act is recorded by
the government, individuals might be reluctant to visit certain websites or
engage in certain activities in fear of being recorded and later flagged by the
government. Although over-deterrence is a risk, procedural safeguards as
articulated below should reduce this chilling effect, as the access to
information will be regulated by the Fourth Amendment.
C.
Acquisition v. Access
There are two distinct points where a potential violation of this privacy
interest in information can occur: during initial acquisition of information and
during access of information.398 Information acquisition usually occurs in
increments as pieces of information gathered from various sources.399
Information access is a more continuous endeavor. Gathered information data
points are collectively displayed or analyzed for patterns and meaningful data
sets.400
Information access fits the definition of search better than information
acquisition.401 Only during access to information does the individual or the
automated program “try to find someone or something.”402 At this stage, the
officer or the computer program searches individual data points and fits them
into categories that reveal other information of interest.403
During the gathering stage, information is copied in bits and pieces.404
As proponents of mosaic theory suggest, there is a problem with gathering
individual pieces, which would amount to an unreasonable search.405 Yet, the
sequence of events that goes from individual data acquisition to the aggregated
data simply does not fit into any literal meaning of search.406 As discussed
above, most acquisition methods do not distinguish between the information
398. See generally Mark Taticchi, Redefining Possessory Interests: Perfect Copies of Information as
Fourth Amendment Seizures, 78 GEO. WASH. L. REV. 476, 477–78 (2010) (discussing the expected rights
individuals have in their information and how access and duplication of information is problematic vis-à-vis
Fourth Amendment jurisprudence).
399. See generally Rakesh Sharma, Google’s Acquisition of Nest and Your Privacy, FORBES (Jan. 13,
2014, 9:07 PM), http://www.forbes.com/sites/rakeshsharma/2014/01/13/googles-acquisition-of-nest-and-yourprivacy/#1df42ce3fdf5 (providing an example of incremental acquisition of personal data).
400. Id. (“Google can easily combine this data set with other services to gain an even more complete
picture of your movements.”).
401. See MERRIAM-WEBSTER ONLINE DICTIONARY (2015), http://www.merriam-webster.com/
dictionary/search (last visited Mar. 9, 2016) (providing the definition of “search”).
402. Id.
403. See generally Doug Wyllie, How ‘Big Data’ Is Helping Law Enforcement, POLICEONE.COM (Aug.
20, 2013), http://www.policeone.com/police-products/software/Data-Information-Sharing-Software/articles/
6396543-How-Big-Data-is-helping-law-enforcement/ (discussing how data analytics can improve law
enforcement and the role of the crime analyst in utilizing data sets).
404. See Christina DesMarais, Who’s Gathering Your Personal Information?, TECHLICIOUS (Mar. 14,
2014),
http://www.techlicious.com/blog/whos-gathering-your-personal-information/
(illustrating
the
fragmented way personal information and online data is aggregated by data collectors).
405. See Kugler and Strahilovitz, supra note 365, at 5 (illustrating Mosaic Theory proponents’ concerns
over the piecemeal collection of a private individual’s information).
406. See generally Kerr, supra note 304, at 315–20 (articulating a historical approach to applying Fourth
Amendment law to searches and seizures and its poor fit to questions and problems arising in Mosaic Theory).
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until it is processed.407 Even though it is possible to create a program to only
store information that is relevant,408 everything is gathered and analyzed, and
the irrelevant data is deleted.409
At the most fundamental level, in order to be able to copy data stored on a
computer hard drive, the computer needs to read each bit to copy.410 However,
the individual bit does not reveal anything, as it is either a one or zero.411 Only
when those zeros and ones are put together can the machine make sense of
it.412 However, during the copying stage the act of looking at each individual
bit does not reveal any information; therefore no search occurs.413
The reason why there is no search at any individual time on the public
streets—that there is no reasonable expectation of privacy in that
information—is the same for the online context. There is no individual
expectation of privacy in each individual piece of information. However, the
reason why the aggregated data feels like a violation is not because the
information is out there, it is because the information is accessed all at the
same time.414 Information sitting in computer hard drives throughout the
country in the servers of various companies does not violate any privacy
interests.415 Similarly, when the government gathers data, if it is just sitting in
the computer hard drives of massive data centers, no violation occurs because
no information is gained.
When the information is accessed in a meaningful format, only then a
violation occurs because it reveals information protected by the privacy
interest.416
D.
How Much Is Too Much
The difficulty in characterizing the reasonable expectation of privacy in
information, or any other theory that depends on a mosaic theory—that
407. FELDMAN & SANGER, supra note 201, at 64 (“Probably the most common theme in analyzing
complex data is the classification, or categorization, of elements. Described abstractly, the task is to classify a
given data instance into a prespecified set of categories.”).
408. Relevant information could be a keyword, particular name, a phone number, or an address.
409. See Charles Arthur, What Is Google Deleting Under the ‘Right to be Forgotten’—and Why?,
GUARDIAN (July 4, 2014, 12:46 PM), http://www.theguardian.com/technology/2014/jul/04/what-is-googledeleting-under-the-right-to-be-forgotten-and-why (providing an example of a large data-collecting company
sorting its collected information and discarding what is irrelevant).
410. How Coding Works, CODECONQUEST, http://www.codeconquest.com/what-is-coding/how-doescoding-work/ (last visited Mar. 9, 2016) (“A computer can only understand two distinct types of data: on and
off. In fact, a computer is really just a collection of on/off switches (transistors). Anything that a computer can
do is nothing more than a unique combination of some transistors turned on and some transistors turned off.”).
411. Each digit in binary code represents one transistor. Id. Binary code is based on ones and zeros
arranged in combinations of eight. Id. A single one or zero is only meaningful when it is read relative to the
other seven digits that comprise a byte. Id. (“Modern computers contain millions or even billions of transistors,
which means an unimaginably large number of combinations.”).
412. Id.
413. Chris Woodford, Hard Drives, EXPLAINTHATSTUFF, http://www.explainthatstuff.com/
harddrive.html (last updated Aug. 24, 2015).
414. Id.
415. Id.
416. The question remains, however, whether a violation occurs when an automated computer program
searches the computer or only when a government official reviews the computer’s findings.
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individual information obtained without violating the Fourth Amendment can
nevertheless violate the Fourth Amendment in the aggregate—is made clear by
the next logical question: How much data is too much? A local police
department collecting traffic camera images from a single town’s traffic lights
and gathering travel information about the drivers is much different than the
mass surveillance and collection of phone records by NSA.
The issue is when does data become “aggregated?” “[A]gencies and
departments maintain almost 2000 databases, including records pertaining to
immigration, bankruptcy, Social Security, military personnel, as well as
countless other matters . . . . States maintain public records of arrest, births,
criminal proceedings, marriages, divorces, property ownership, voter
registration, workers compensation, and scores of other types of records,”
including licensing records “on numerous professionals such as doctors,
lawyers, engineers, insurance agents, nurses, police, accountants, and
teachers.”417 This information as it is held at individual agencies does not pose
a problem, as the “practical obscurity”418 still keeps the information that is
revealed by the collective analysis of that individual information private.419
The single biggest concern that relates to the privacy concern of the
aggregated data is the practical obscurity. Information revealed to third
parties,420 the tracking of movement in public streets,421 and information
shared on public websites, can all individually be obtained by various methods
such as FOIA or by subpoena from various entities that store such
information.422 Only when the practical obscurity is removed does the data
become aggregated.423 Therefore, the data becomes aggregated when a system
is set up for accessing that information from a single access point.424
This formulation of aggregation therefore allows for flexibility on
government agencies’ procedures for digitizing records and storing
information relevant to the agencies’ function, while protecting against the
aggregated access to that information. This formulation does not depend on
the agencies’ purpose either. Even if an agency has a completely legitimate
purpose, such as the IRS setting up a system to control the accuracy of
individuals’ tax filings, when the system acts to collect information from
various sources, or allows access to that information from a single access
point, the data becomes aggregated for the purposes of the Fourth Amendment.
E.
Level of Suspicion
The level of suspicion to access the aggregated information should be a
417. Daniel J. Solove, Privacy and Power: Computer Databases and Metaphors for Information
Privacy, 53 STAN. L. REV. 1393, 1403 (2001).
418. Dep’t of Justice v. Reporters Comm. for Freedom of the Press, 489 U.S. 749, 762 (1989).
419. Id.
420. Smith v. Maryland, 422 U.S. 735, 744 (1979); Klayman v. Obama, 957 F. Supp. 2d 1, 40 (2012).
421. United States v. Jones, 132 S. Ct. 945, 946 (2012).
422. Id.
423. Id.
424. Under this theory there would be a question whether a computer program that analyzes only data
available on the Internet would fall under such definition of single access point.
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preponderance of the evidence, a standard higher than probable cause. The
intrusion into an individual’s privacy interest in the aggregated data is much
higher than a traditional search because the access to aggregated data reveals
much more information than a traditional search of a house.425
“The touchstone of the Fourth Amendment is reasonableness . . . .”426 As
the Court articulated in Terry v. Ohio,427 when the intrusion into one’s
protected interest is low, a lower standard of suspicion is sufficient to justify a
search and seizure.428 In the case of access to aggregated data, the weights are
reversed. The intrusion into the privacy interest of the individual is much more
significant than the brief investigatory stop. It implicates information
regarding the entire life of the individual.429 Although the national security
interest is also much higher than shoplifting, the Fourth Amendment binds
every law enforcement officer, from the county constable to the NSA.430 For
that end, even a probable cause standard may fall short of providing a
justification for the intrusion.
The level of privacy interest in electronic data is somewhat recognized in
Riley v. California where the Court held that a warrantless search of a cell
phone incident to arrest was unreasonable.431 Although the Court did consider
that a warrant issued by a magistrate judge would be sufficient, the aggregated
information is even more intrusive than the contents of the cell phone.432 The
aggregated information by its “nature precludes [it] from being the object of a
reasonable search.”433 Therefore, when the search is unreasonable, even the
warrant issued upon probable cause would be unreasonable.434 Due to the
nature of information gathered from a search of aggregated data, and its
tendency to reveal much more information than a search of a house or work
place, access to that information deserves a finding of a higher suspicion level
than probable cause.
In that regards, the preponderance of evidence standard would allow a
greater protection to the information while balancing the needs of law
enforcement in the investigation of targeted individuals. Even though probable
cause to arrest an individual or search his house will be satisfied before the
access to aggregated information is allowed, the information gathered from the
aggregated data will be much more than a search of the house or interrogation
of the individual.435
425. How
Smart
Meters
Invade
Individual Privacy,
SMART
GRID
AWARENESS,
http://smartgridawareness.org/privacy-and-data-security/how-smart-meters-invade-individual-privacy/
(last
visited Mar. 9, 2016).
426. United States v. Knights, 534 U.S. 112, 118 (2001) (citing Wyoming v. Houghton, 526 U.S. 295,
300 (1999)).
427. 392 U.S. 1, 9 (1968) (citing Elkins v. United States, 364 U.S. 206, 222 (1960)).
428. Id. at 26.
429. See United States v. Jones, 132 S. Ct. 945, 954 (Sotomayor, J., concurring).
430. U.S. CONST. amend. IV.
431. 134 S. Ct. 999 (2014).
432. Id.
433. Warden v. Hayden, 387 U.S. 294, 303 (1967).
434. Id.
435. Id.
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F.
131
Efficient Law Enforcement, Potential for Abuse
Use of technological developments increases the efficiency of law
enforcement.436
Until recent years, the amount of information law
enforcement officers could gather was limited by the capabilities of the
individual officers. It was about asking questions, physically following a
person in the streets, and stakeouts. Most surveillance methods were
procedurally inefficient.437 The ease of obtaining information, however,
should not be a case against such techniques. On the contrary, it should be a
case for the use of such techniques.
Technological data analysis methods allow for more automation.
Automation can be taught438 or programmed without relation to individuals’
constitutionally protected characteristics such as race, national origin, and
gender. Even though a program can be tweaked to take into account such
characteristics, it would be easier to show these violations than the current
struggle regarding law enforcement agencies’ motives in enforcing the law.
Moreover, when there is a neutral reason for the disparate impact based on a
characteristic, it can be shown with reference to the program.
As seen in the example of Canadian license plate readers, most violations
identified by the system will go untreated because of administrative
limitations.439 Yet, automation would allow more efficient distribution of law
enforcement resources. For example, the automated software could be
programmed to rank or classify findings based on offense types, the distance
from an on-duty police officer, or the evidentiary value that gives rise to a
suspicion. This allows for objective determinations in crime investigations
while leaving enough discretion to compensate for the shortcomings of the
software.
“Great power comes with great responsibility,”440 yet we still see on the
television the abuse of power by the government. These abuses range from the
reports of NSA employees exchanging intimate photos,441 to everyday police
officer brutalities,442 to systematic police department cultures.443 The primary
436. K.A. Taipale, Data Mining and Domestic Security: Connecting the Dots to Make Sense of Data, 5
COLUM. SCI. & TECH. L. REV. 2 (2003) (“The efficiencies inherent in data aggregation itself cannot be denied;
indeed, it is these efficiencies that provide the impetus for developing and employing data aggregation
technologies in the first place.”); see also Daniel J. Solove, A Taxonomy of Privacy, 154 U. PA. L. REV. 477,
506–11 (2006) (explaining more on the problems of data aggregation).
437. During oral arguments in Jones v. United States, Chief Justice Roberts asked the government’s
lawyer Mr. Dreeben whether the Constitution would allow the FBI to install a GPS device on their cars.
438. Machine learning algorithms are common in data mining.
439. Douglas Quan, ‘You Are Being Tracked’: How Cities Use License-Plate Scanners to Create Vast
Databases of Vehicle Sightings, NAT’L POST (July 14, 2014), http://news.nationalpost.com/news/canada/youare-being-tracked-how-cities-use-licence-plate-scanners-to-create-vast-databases-of-vehicle-sightings
(last
updated Jan. 24, 2016, 10:21 PM).
440. SPIDER-MAN (Marvel Entertainment 2002).
441. Steve Dent, Snowden Shows John Oliver How the NSA Can See Your Dick Pics, ENGADGET (Apr. 6,
2015), http://www.engadget.com/2015/04/06/john-oliver-snowden-interview/.
442. ANDREA J. RITCHIE, ESQ. ET AL., U.N. COMM. ON THE ELIMINATION OF RACIAL DISCRIMINATION, IN
THE SHADOWS OF THE WAR ON TERROR: PERSISTENT POLICE BRUTALITY AND ABUSE OF PEOPLE OF COLOR IN
THE UNITED STATES (Dec. 2007).
443. U.S. DEP’T OF JUSTICE, CIVIL RIGHTS DIV., INVESTIGATION OF THE FERGUSON POLICE
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concern for the Fourth Amendment—the dislike of general warrants—can be
implicated as the ease of accessing information stored in a data center
increases and as the loss of “practical obscurity”444 “magnifies and enhances
government power”445 and creates the temptation to abuse such power.446
Although these cultural systematic cultural problems are horrifying, it
does not involve the Fourth Amendment analysis. The Fourth Amendment
“protects individual privacy against certain kinds of governmental intrusion”447
but not others.448 Further, “[i]t is the exploitation of technological advances
that implicates the Fourth Amendment, not their mere existence.”449 Therefore
the “access” to the information rather than the gathering of the information is
what implicates the Fourth Amendment.
V. RECOMMENDATION AND CONCLUSION
The speed at which information is gathered and analyzed is beyond what
the people of 1776 could have imagined. This information, in the aggregate,
allows for effective law enforcement and other government activities.
However, the removal of practical obscurity regarding the access to
information creates significant privacy concerns. The Fourth Amendment’s
protection against unreasonable searches and seizures is one of the
constitutional safeguards against a particular governmental intrusion.450 There
is information stored in databases of various governmental agencies and
private corporations that can be obtained by the government without any
Fourth Amendment implications.451 However, when a system is created to
remove the practical obscurity of obtaining the aggregated information and
allow access from a single access point when the data is aggregated, then the
access to that aggregated information in such a manner implicates the Fourth
Amendment far beyond the use of any other device.452 Regardless of the
agencies’ purpose in creating such a system, when the system is capable of
obtaining such information, the Fourth Amendment will be violated. Further,
the probable cause standard of the Fourth Amendment is dwarfed by the
tremendous privacy intrusion, and even a warrant issued upon a finding of
probable cause does not satisfy the reasonableness requirement of the Fourth
DEPARTMENT, http://www.justice.gov/sites/default/files/opa/press-releases/attachments/2015/03/04/ferguson_
police_department_report.pdf; see also Ta-Nehisi Coates, The Gangsters of Ferguson, ATLANTIC (Mar. 5,
2015), www.theatlantic.com/politics/archive/2015/03/The-Gangsters-Of-Ferguson/386893/ (examining results
of the Department of Justice’s report on the shooting of Michael Brown and investigation into the Ferguson
Police Department’s practices).
444. Dep’t of Justice v. Reporters Comm. for Freedom of the Press, 489 U.S. 749, 762 (1989).
445. Taipale, supra note 436.
446. Id.
447. Katz v. United States, 389 U.S. 347, 350 (1967).
448. See id. at 363 n.** (stating as an example that “[t]he Fourth Amendment does not protect against
unreliable (or law-abiding) associates.” (citation omitted)).
449. United States v. Karo, 468 U.S. 705, 712 (1984).
450. Katz, 389 U.S. at 350.
451. Id. Under this theory there would be a question whether a computer program that analyzes only data
available on the Internet would fall under such definition of single access point.
452. Id.
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HOW MUCH DATA CAN THE FOURTH AMENDMENT HOLD
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Amendment.453 Hence, only upon a preponderance of evidence can a law
enforcement agency have access to aggregated data.
As with any other area where privacy is concerned, Congress could easily
regulate the access to aggregated information and create procedural safeguards
that allow a degree of privacy while leveraging the technological power to
detect and prevent crime. As Justice Alito suggested, the use of many data
gathering and analyzing technology is not that different from traditional
wiretapping, yet they are much more powerful.454 The Fourth Amendment’s
protections have been highly debated and have seen a lot of changes in recent
years.
However, the impact of technology on Fourth Amendment
jurisprudence has yet to reach its peak.
453.
454.
U.S. CONST. amend. IV.
United States. v. Jones, 132 S. Ct. 945, 956 (2012) (Alito, J., concurring).